Patent Publication Number: US-2019177046-A1

Title: Plate-shaped structure, a reservoir and method

Description:
The invention relates to a plate-shaped structure for cultivating one or more plants, comprising a generally flat upper surface, especially for connecting to a reservoir. 
     Such a plate-shaped structure is e.g. known from WO 2012/081980. Both the plate-shaped structure and the reservoir can be made from paper material rendering the plant irrigation system very cheap. The known plate-shaped structure is provided with a central opening for surrounding a plant to be protected. 
     Although the plate-shaped structure and the reservoir provide satisfying results in practice, there is an ongoing need to increase its functionality. 
     It is an object of the invention to provide a plate-shaped structure according to the preamble wherein the functionality increases. Thereto, the generally flat upper surface is provided with
     a single or a multiple number of cavities for receiving plant material;   a drain opening provided with a sidewall extending downwardly in a tapered manner for entering moisture that is received on the generally flat upper surface downwardly   a cap located freely in the drain opening, so as to allow water to seep down between the cap and the sidewall of the drain opening, the cap having a weight greater than the weight of a body of water with the same volume of the cap, the cap having an outer contour that is in conformity with a cross sectional geometry of the downwardly tapered sidewall of the drain opening.
 
The cavity may have a sidewall and a bottom portion, wherein the bottom portion includes an aperture or slits traversing the plate-shaped structure. Then, not only a single plant or two plants surrounded by a central opening of a known plate-shaped structure can be cultivated, but also further plant material may be cultivated, e.g. seed material.
   

     By providing one or more drain opening, each with a cap, evaporation of precious moisture is counteracted while still offering a capacity of harvesting rainwater during a heavy rain shower. A cap provided freely in the drain opening (i.e. lying circumferentially surrounded by the sidewall of the drain opening without being mechanically fixed to it) is used to enable water to seep down to a reservoir below the plate-shaped structure, while limiting the area from which water loss due to upward evaporation from the reservoir, i.e. to provide a siphon function. 
     Preferably, a water seep rate of at least 0.2 and more preferably 0.5 or one liter water per minute is provided for the plate-shaped structure. It has been found that roughness of the surface of the cap and/or the side wall where they are in contact with each other makes it possible to realize such a rate of seepage. The roughness provides for channels for water seepage, as can be seen by observing the seepage. Side walls made of paper have been found to realize a sufficient rate of seepage. If desired, the seepage rate may be increased by roughening the surface of the cap and/or sidewall, or by providing dedicated channels in the surface of the cap and/or sidewall. 
     In an embodiment the plate-shaped structure may be entirely formed by paper material. 
     By providing a cap that is heavier than water freely in a drain opening so that water seeps between the cap and the sidewall of the drain opening, it is counteracted that the generally flat upper surface remains humid and collapses. 
     Use of a cap that is heavier than water reduces the risk that the cap can be blown off. It has been found that this provides for a closing function that is compatible with use of paper structures, wherein e.g. screw or clamp closures are difficult to realize. 
     As an example, the cap may be implemented as a clay ball. When a cap is used that does not float in water, there is a risk that the cap will rotate to an arbitrary orientation, which could compromise the closing function of the cap to reduce evaporation. Use of a ball shaped cap has the advantage that the rotation of the cap will not affect the closing function of the cap. When caps of other shapes are used, it may be preferable to use a shape of which the center of mass is below the edge of the cap that is in contact with the side wall of the drain opening. 
     Use of a cap that is heavier than water in contact with a paper sidewall can be applied more generally e.g. to sidewalls of drinking cups to reduce evaporation. 
     By providing the above-described drain opening cooperating with the cap such as a ball-shaped cap, the overall structure of the plate-shaped structure remains intact, also during wet atmospheric conditions, thus counteracting evaporation of pre-collected moisture. 
     The plate-shaped structure can thus be provided such that weight and/or damage of water, sand and/or soil can be resisted. 
     According to yet a further aspect, the plate-shaped structure further comprises a stay defining a predefined offset between opposite sections of the central opening. By providing a stay defining a predefined offset between opposite sections of the interior side wall top edge of the reservoir, any deformation of the interior side wall inwardly into the area surrounded by said interior side wall is counteracted, thereby maintaining the shape and orientation of the interior side wall so that the connection is also maintained and the occurrence of any undesired opening in the connection is counteracted. Then, evaporation of precious moisture from the reservoir is counteracted. 
     In an embodiment the structure covers a reservoir for storing moisture for moistening the plant, the reservoir comprising an upwardly extending exterior sidewall the generally flat upper surface including a downwardly oriented flange at the periphery of the generally flat upper surface, for receiving the upwardly extending exterior sidewall of the reservoir, the downwardly oriented flange and the upwardly extending exterior sidewall comprising corresponding protrusions and openings for receiving the protrusions. The protrusions may be on the flange and the openings on the reservoir, or vice versa, or the different protrusions may be provided on the flange and the reservoir respectively and corresponding openings vice versa on the reservoir and the flange. When the protrusions extend to the openings they secure the generally flat upper surface to the reservoir. The openings may contain detents for detaining the protrusions in the openings, e.g. an edge of the lower side of an opening on the flange may extend below a protrusion on the reservoir, or an edge of the lower side of an opening on the reservoir may extend above a protrusion on the flange Similarly, the protrusions may form detents for detaining the protrusions in the openings. This may be used also when a floating cap is used instead of the cap that is heavier than water. 
     In a particular embodiment, the plate-shaped structure is arranged for collecting moisture. 
     Further advantageous embodiments according to the invention are described in the following claims. 
     The invention also relates to a reservoir. 
     Further, the invention relates to a method. 
    
    
     
       By way of example only, embodiments of the present invention will now be described with reference to the accompanying figures in which 
         FIG. 1  shows a schematic perspective view of a plate-shaped structure for cultivating one or more plants according to the invention; 
         FIG. 2  shows a schematic perspective view of a reservoir according to the invention; and 
         FIG. 3  shows a schematic perspective cross sectional view of the plate-shaped structure of  FIG. 1  and the reservoir of  FIG. 2  in assembled state; 
         FIG. 4  shows an upper schematic perspective view of a second embodiment of a plate-shaped structure for cultivating one or more plants according to the invention; 
         FIG. 5  shows a lower schematic perspective view of the plate-shaped structure of  FIG. 4 ; 
         FIG. 6 a    shows a perspective schematic view of a covering cap positioned in an upper portion of the drain opening of the plate-shaped structure shown in  FIGS. 4 and 5 ; 
         FIG. 6 b    shows a perspective schematic view of a cap positioned in the drain opening of the plate-shaped structure shown in  FIGS. 4 and 5 ; 
         FIG. 7  shows a schematic cross sectional view of the drain opening of the plate-shaped structure shown in  FIGS. 4 and 5  with a covering cap; 
         FIG. 8  shows an upper schematic perspective view of a third embodiment of a plate-shaped structure for cultivating a plant according to the invention; 
         FIG. 9  shows a lower schematic perspective view of the plate-shaped structure of  FIG. 8 ; 
         FIG. 10  shows a schematic perspective view of a second embodiment of a reservoir according to the invention; 
         FIG. 10A-C  show details of rims, protrusions and detents to fix the cover; 
         FIG. 10D  shows a schematic perspective cross sectional view of a drain opening provided in a fourth embodiment of a plate-shaped structure according to the invention; 
         FIG. 10E  shows a schematic perspective cross sectional view of a cavity provided in the plate-shaped structure of  FIG. 10D ; 
         FIG. 10F  shows a schematic perspective cross sectional view of the plate-shaped structure of  FIG. 10D  and a third embodiment of a reservoir according to the invention in an assembled state and provided with a funnel; 
         FIG. 10G  shows a schematic perspective view of the assembled plate-shaped structure and reservoir of  FIG. 10F  receiving a number of pots; 
         FIG. 10H  shows a schematic perspective view of the reservoir of  FIG. 10F ; 
         FIG. 10I  shows a detailed schematic perspective view of the assembled plate-shaped structure and reservoir of  FIG. 10F ; 
         FIG. 10J  shows a schematic perspective view of the plate-shaped structure of  FIG. 10D ; 
         FIG. 11  shows a perspective schematic view of the plate-shaped structure of  FIG. 4  and the reservoir of  FIG. 10  in an assembled state, 
         FIG. 12  shows a perspective schematic view of further plate-shaped structure and a further reservoir in an assembled state. 
         FIG. 13  shows a perspective schematic view of the plate-shaped structure with details of the flange and generally flat upper surface containing openings and detents for receiving protrusions. 
         FIG. 14  shows a schematic side-view of the plate-shaped structure of  FIG. 13  with details of the flange and generally flat upper surface containing openings and detents for receiving protrusions. 
         FIG. 15  shows a schematic top-view of the plate-shaped structure of  FIG. 13  with details of the generally flat upper surface containing openings and detents. 
         FIG. 16  shows a schematic cross-sectional view of the plate-shaped structure of  FIG. 13  engaging a reservoir with a rolled-lip protrusion, detailing a clamping connection between the cover openings and detents and the protrusion of the reservoir. 
         FIG. 17  shows a schematic top-view close-up of the plate-shaped structure of  FIG. 15  with details of the flange, the generally flat upper surface, the opening and the detent. 
         FIG. 18  shows a schematic cross-sectional view of an assembly of the plate-shaped structure of  FIG. 13  assembled with a cup reservoir, with details of the flange and the generally flat upper surface. 
     
    
    
     It is noted that the figures show merely preferred embodiments according to the invention. In the figures, the same reference numbers refer to equal or corresponding parts. 
       FIG. 1  shows a schematic upper perspective view of a plate-shaped structure for cultivating one or more plants according to the invention. The structure is implemented as a collection structure  1 . The collection structure  1  comprises a water recovery surface  2 . Further, the collection structure  1  is provided with a central opening  3   a,b  having a rim  4  for at least partly sideways surrounding a young plant. The collection structure  1  also includes a hole  5 , for refilling a reservoir located below the collection structure  1 . Further, the collection structure  1  comprises an exterior rim  6  having a profile that is corrugated in a direction mainly transverse with respect to a plane wherein the water recovery surface  2  extends. The collection structure  1  is preferably formed as a single cover module, preferably forming an airtight cover. During operation, the collection structure  1  is connected to a reservoir  10  for sealing the interior of the reservoir. 
     It is noted that the refilling hole  5  can be implemented as the drain opening  35  described in more detail referring to  FIG. 4 . 
       FIG. 2  shows a schematic upper perspective view of a reservoir  10  according to the invention. The reservoir  10  has an upwardly extending exterior side wall  11  having a exterior top edge  15  facing outwardly and an interior side wall  12  extending upwardly having a top edge  13  for forming a tube for at least partly sideways surrounding the young plant. The reservoir  10  has also a bottom  14  extending between the exterior and interior side wall  11 ,  12 . Advantageously, the reservoir  10  can be provided with irrigation means for delivering moisture present in the reservoir  10  to a subsoil located there below. As an example, the irrigation means may include a single or a multiple number of capillary cords, injection needles or membranes traversing the bottom  14  or a side wall  11 ,  12  of the reservoir  10 . The geometry of the rim  4  of the central opening  3   a,b  of the collection structure  1  corresponds with the geometry of the top edge  13  of the interior side wall  12  of the reservoir  10 , such that when the connection structure  1  is connected to the reservoir  10 , in an assembled state, the central opening rim  4  of the collection structure  1  cooperates with the top edge  13  of the interior side wall  11  of the reservoir  10 , preferably in a sealing way, e.g. using a snap fitting. 
     According to an aspect, the collection structure  1  or the reservoir  10  or both the collection structure  1  and the reservoir  10  may comprise a stay  20  defining a predefined offset PO between opposite sections  13   a,b  of the top edge  13  of the interior side wall  12 . 
     In the shown embodiment, both the collection structure  1  and the reservoir  10  include such a stay  20   a,b.  The stay  20   a,b  is here implemented as a strip integrally formed with the water recovery surface  2 , forming a bridge between opposite sections. In the collection structure  1 , the stay  20   a  interconnects opposite rim sections  4   a,b  for defining the predefined offset PO when the collection structure  1  is connected to the reservoir  10 . Similarly, in the reservoir  10 , the stay  20   b  interconnects opposite sections  13   a,b  of the interior side wall top edge  13 , thus defining the predefined offset PO there between. In alternative embodiments, only the collection structure or the reservoir  10  is provided with a stay  20   a,b.  Further, the stay  20  may be implemented in another way, e.g. as a ridge or flange. It is noted that, in principle, the stay  20  can be integrally formed or partially integrally formed, e.g. integrally formed with a part of the collection structure. Further, the stay  20  can be formed as a single or a multiple number of discrete elements, e.g. as a separate block element mounted or clampingly positioned between opposite rim sections  4   a,b  or between opposite top edge sections  13   a,b,  respectively. 
     In the shown embodiment of the reservoir  10 , the top edge  13  of the interior side wall  12  mainly surrounds a bar-bell shaped area, i.e. the top edge  13  has bar-bell contour. The stay  20  interconnects opposite edge sections  13   a,b  having the shortest mutual distance, i.e. halfway end portions of the bar-bell shaped area. 
     In an alternative embodiment, the top edge  13  of the interior side wall  12  mainly surrounds or encloses a disc-shaped area, a square-shaped area or an elongated area. Further, the top edge  13  of the interior side wall  12  may surround an area having an open end, such as an U-shaped area. 
     Preferably, the central opening rim  4  of the collection structure  1  and the top edge  13  of the interior side wall  12  of the reservoir  10  form an airtight connection, e.g. using a snap fitting, so that escape of moisture or humid air is minimized or even reduced to zero or almost zero. In an advantageous manner, the exterior rim  6  of the collection structure  1  cooperates with the exterior top edge  15  of the reservoir  10 , preferably in an airtight connection, when the collection structure  1  is connected to the reservoir  10 . Then, the reservoir can be sealed from the atmosphere. Preferably, a single or a multiple number of bleeding openings can be provided in the reservoir to counteract that the process of delivering moisture to the subsoil is hindered by a sub-pressure of air in the reservoir  10 . 
     As shown in  FIG. 2 , the exterior top edge  15  of the reservoir exterior side wall  11  mainly forms a square contour. Similarly, the exterior rim  6  of the collection structure  1  has a corresponding contour. In a connected state, exterior rim corner protrusions  15   a  of the collection structure  1  clampingly engage through corresponding corners  6   a  of the exterior side wall top edge  15 , e.g. by firmly connecting the corresponding corners with each other, thereby stretching the collection structure between the corners of the exterior side wall top edge  15 , thereby improving the air sealing behaviour of the connection between the connection structure  1  and the reservoir  10 . Further, a chance is reduced that the connection structure  1  is blown away by gale or vacuum forces. 
     Preferably, the collection structure and the reservoir are detachably coupled, thereby providing a modular design enabling re-use of modular components. However, the collection structure and the reservoir can also be formed to provide a permanent coupling, e.g. for enhancing airtight sealing properties. 
       FIG. 3  shows a schematic perspective cross sectional view of a plant irrigating system including the reservoir  10  and the collection structure  1  according to the invention. In the shown embodiment, the exterior rim  6  of the collection structure  1  surrounds the top edge  15  of the exterior side wall  11  of the reservoir  10 . The exterior rim  6  preferably overlaps the top edge  15  at opposite sides thereof, thereby providing a clamping connection. The top edge  15  of the reservoir&#39;s exterior side wall  11  may have a bended end portion  15   a  that is mainly parallel to the bottom  14  of the reservoir  10  and extends outwardly, to enhance the connection with the collection structure  1 . Alternatively, the top edge  15  is flat and extends upwardly. After connecting the collection structure  1  to the reservoir  10  the material of the collection structure may shrink, especially when exposed to a sun beam, thereby further strengthening the connection between the connection structure  1  and the reservoir  10 . 
     In a very advantageous manner, the collection structure and/or the reservoir are manufactured from cellulose and/or paper material and/or plastic such as biodegradable plastic. The paper material may include cardboard, cellulose, such as paper tissue, paper foam and/or fiber paper. 
     As an example, the fiber paper may include cellulose made from coconut fiber, cotton fiber, banana fiber, jute fiber, wool fiber, straw fiber, grass fiber, hemp fiber, kenaf fiber, wheat straw paper, sunflower stalks fiber, rags fiber, mulberry paper and/or kozo. 
     The biodegradable plastic can be based on petroleum based plastics or renewable raw materials, both including a biodegradable additive. Plastic can be based on petroleum as raw material. 
     As an alternative to the embodiments shown in  FIGS. 4, 5, 8, 9, 11 and 12 , the water recovery surface  2  can be substantially funnel-shaped. Further, the water recovery surface  2  may have a more complex structure. As an example, the water recovery surface may comprise a receiving surface which during use makes a first angle with respect to the orientation of gravity, and a collecting surface bounding a bottom edge of the receiving surface, which collecting surface during use makes a second angle with respect to the orientation of gravity, wherein the first angle is smaller than the second angle. As an example, the water recovery surface has a corrugated profile, e.g. as described in patent publication WO 2009/078721. 
     It is noted that the moisture flowing structure for flowing collected moisture from the water recovery surface  2  downwardly may include an inflow opening and/or an inflow pipe extending from the water recovery surface  2  downwardly into the reservoir  10 . 
     When the collection structure  1  is connected to the reservoir  10 , a plant irrigation system is formed for protecting a young plant or tree planted in the area surrounded by the interior side wall  12  of the reservoir  10 . 
     Preferably, material forming the collection structure and the reservoir includes water impermeable material and/or is provided with a liquid impermeable coating, e.g. on the inner and/or outer side. Further, the forming material can be coated with a biodegradable layer, preferably having a pre-determined thickness so that a desired degree of degradedness can be set. Alternatively or additionally, the degradedness of the biodegradable layer can be set by including a dosed amount of conserving material. Further, the degradedness can be set by localizing specific parts at specific heights with respect to the ground level. In general, material in the collection structure can be optimized to degrade later than material in the reservoir, due to adding additives that slow down the degrading process. This way the collection structure can function during a number of years as a ground cover and help to prevent evaporation of water, to prevent growing of competitive weeds and to add nutrients to the plant over a longer period of time. 
     Preferably, the base material of the collection structure and/or reservoir includes specific material that is integrated in or bound to the base material e.g. using a neutral glue  66  for a specific time period and is then disseminated into the environment, due to degradable properties of the base material. Here, the word “neutral” is to be understood as having no or only a negligible influence on the germination of plant material. In the embodiments shown in  FIG. 3  the reservoir  10  is provided with a neutral glue layer  66  for providing the specific material to the reservoir  10 . By setting the degradedness of the base material, the degree of dissemination of the specific material can be determined. In this way, the plate-shaped structure  1  and the reservoir  10  can function as slow release carriers for plant growth stimulators and repellents against animals, funguses and/or insects. In this respect it is noted environmental parameters, such as wind, moisture etc. may influence the degradedness of the base material. 
     As an example, the specific material may include nutrients, aromatic substances, flavourings, (artificial) fertilizer or michorizae, anti-fungal material and/or at least one insecticide, e.g. nicotine for chasing away harmful animals such as termites, and/or fungi. Further, the specific material may include seeds, symbiotic bacteria, eggs, fungi and/or spores that may germinate after leaving the base material, thereby improving the biodiversity of the irrigating system. As an example, the reservoir may include a first specific material and the collection structure may include a second specific material, as it degrades later. The number of seeds, fungi and/or spores can be determined before integrating in or attached to the base material, e.g. using glue  66 . 
     By integrating the specific material in the base material, the base material serves as an agent for the specific material that disseminates in a dosed manner. By integrating in or attaching the specific material to the base material, the base material serves as a slow release agent for the specific material that inoculates in a dosed manner. 
     Alternatively or additionally, the specific material can be added into the reservoir, prior, during or after planting a young plant to be protected by the collection structure and/or reservoir, e.g. in combination with an amount of soil placed in the reservoir so that the specific material is provided to the subsoil and the root structure of the young plant via the dosed flow of water from the reservoir. 
       FIG. 4  shows an upper schematic perspective view of a second embodiment of a plate-shaped structure for cultivating a plant according to the invention.  FIG. 5  shows a lower schematic perspective view of the plate-shaped structure of  FIG. 4 . The plate-shaped structure  1  comprises a generally flat upper surface  30  provided with three cavities  31 ,  32 ,  33 , each of the cavities having a sidewall  41 ,  42 ,  43  and a bottom portion  51 ,  52 ,  53 . The cavities may have various shapes, such as a rounded, oval, square, rectangular or diamond shape. The bottom portion includes aperture  61 ,  62 ,  63  e.g. in the form of holes or slits traversing the plate-shaped structure  1  to enable moisture communication between the cavities  31 ,  32 ,  33  and the inner space  80  of the reservoir  10 . The sidewalls  41 ,  42 ,  43  of the cavities  31 ,  32 ,  33  are tapered downwardly. 
     When using the plate-shaped structure, plant material such as seeds, seedlings, cuttings, rooted cuttings, plug plants, vegetables and/or pot plants can be provided in the cavities. By providing moisture to said plant material, it may grow in a hydroponic way. Generally, the roots may develop in the humidity and water below them in a reservoir  10 . Depending on a speed of the degrading process of the reservoir  10 , the roots are eventually allowed to penetrate the soil so that the plants that are planted in the cavities can establish themselves. 
     Further, the generally flat upper surface  30  is provided with a central opening  34  having a rim  34   a  for at least partly surrounding the central plant or plants. 
     In an alternative embodiment, the generally flat upper surface  30  does not include a central opening  34 . A reservoir can then be realized without an inner wall  12 . Then, a further cavity may be realized in a central portion of the generally flat upper surface  30 , e.g. for optimizing an amount of plant material to grow in a hydroponic way, to be put on the reservoir  10 . In such a case the generally flat upper surface  30  can not only be used in combination with a reservoir, but can alternatively be applied directly on the soil and this way the plant material can grow directly into the soil instead of in the reservoir  10 . 
     The generally flat upper surface  30  also includes a drain opening  35  provided with a sidewall  45  extending downwardly in a tapered manner for flowing moisture that is received on the generally flat upper surface  30  downwardly, e.g. in the inner space of the reservoir. The drain opening cooperates with a cap such as a ball shaped cap as described below thereby serving an inverted siphon function, allowing fluid to flow through the drain opening while, on the other hand, minimizing any amount of evaporation of moisture stored in the reservoir. In the shown embodiment, the drain opening has a sidewall  45 , no bottom portion. Generally, a bottom portion can be provided, however, such that a pre-defined flow rate of water flowing downwardly can be achieved. In principle, the generally flat upper surface can also be implemented without a drain opening, e.g. when the plate-shaped structure is placed on the soil. 
     The sidewalls  41 ,  42 ,  43  are preferably provided with a multiple number of perforation openings  36 , such as slits, forming a perforation line, so that the bottom portion  51 ,  52 ,  53  of the cavities  31 ,  32 ,  33  can be easily removed. Then, a seed, a rooted plug including plant material or a cutting can be inserted in the cavities. The plug volume seals the opening to the reservoir, thereby counteracting undesired moisture evaporation. 
     As shown in  FIG. 4 , the shown embodiment includes upwardly raised edges  46 ,  47 ,  48  counteracting that moisture received on the generally flat upper surface  30  flows into the cavities  31 ,  32 ,  33 . The edges  46 ,  47 ,  48  surround the corresponding cavities. Advantageously, the edges can be interrupted, in the shown embodiments at corner facing locations  46   a,    47   a,    48   a,  to allow a certain amount of moisture to flow from the plate-shaped structure into the cavities  31 ,  32 ,  33 . Alternatively, the edges  46 ,  47 ,  48  are uninterrupted, forming circular barriers enclosing the cavities  31 ,  32 ,  33  on the plate-shaped structure. An edge is wholly or partly upwardly raised. Now, said moisture entirely flows towards the drain opening  35 , also called inverted siphon, to fill the reservoir  10 . Advantageously, the drain opening is located at a lower portion of the generally flat upper surface to minimize any moisture remaining on the plate-shaped structure  1 . 
     The cavities  31 ,  32 ,  33  are mainly evenly distributed in a circumferential direction on the generally flat upper surface  30 . It is noted that more or less cavities can be provided, e.g. four, five or six cavities, or two cavities. Also, a single cavity can be provided. Further, another cavity distribution can be provided, e.g. a more homogeneous two-dimensional distribution on the general flat upper surface  30 . 
     The cavities, also called cones may have a circular, square, rectangular or polygon geometry. The cones may have an opening in the bottom of approximately  1  to  2  mm diameter. The perforation openings  36  between the sidewalls  41 ,  42 ,  43  and the corresponding bottom portion  51 ,  52 ,  53  forming a perforation line may have an elongated aperture geometry commensurating with the plate-shaped structure. The cones may have two functions: they help that after producing we can stack the collection structures in a horizontal way, especially if the cavities are distributed evenly over the plate-shaped structure. If there would be only an inverted siphon on one topside and no cones on the other top sides, then the collection structures could not be stacked in a horizontal way, but they would be stacked on such a way that the stack would go aside to one direction, away from the side where the inverted siphon is located. The cones may have a second function also. They can be filled with soil, clay particles or a planting pot, e.g. that contain one or more seeds of plants or trees. The collected moisture in the box will evaporate through the bottom opening and make the bottom of the cone humid. In combination with the seed or other plant material this will lead to germination and/or growth. The seed can root through the opening and cellulose of the collection structure and find water in the reservoir. It will then colonize the box and this way lead to the development of plants that surround the plant or tree that was planted in the central opening. Instead of a seed we can also put a cutting through the opening in the cone, with the bottom of the cutting just inside or a little above the water level in the box. The humidity will stimulate the rooting of the cutting. The cones can be either closed, open or with a weak structure in the bottom—made with a needle or through adding less cellulose—so that the root can easier penetrate. The seeds or cuttings in the cones will grow to plants and eventually colonize the surrounding around the planted tree in the middle of the plate-shaped structure. The collection structure can also function as an individual item without the water reservoir. It is then made without a inverted siphon  35  and/or a central opening  34 . Then, the plate-shaped structure does include cones and can be applied directly on the soil. The collected moisture will be directed into the direction of the cones. It will enter the soil through the bottom of the cones. During the rainy period the seeds will germinate—or the cuttings or other plant material will root—and their pivotal roots will penetrate the humid soil below the cones. 
     Optionally, the plate-shaped structure may have a network of small channels on the surface in the form of a spider web, which not only transports the moisture but also function as a ‘bonestructure’ to make the horizontal cover stronger, which has an integrated inverted siphon opening to which the channels transport the moisture, which has a topside on the outside and a topside on the inside that is higher than the channels and the opening, this way taking care that all the collected water enters in the inverted siphon opening. 
     Further, the plate-shaped structure may also be provided with an overflow to prevent the water to enter the middle opening and wash the roots out when the reservoir is completely filled. The central opening  34  may be implemented with various geometries, adapted for different kinds of plants and circumstances. The shape of the central opening may be circular, square, polygon, e.g. with eight corners, rectangular. In an assembled state, the plate-shaped structure  1  and the reservoir  10  are coupled, as described in more detail below. The generally flat upper surface  30  includes a downwardly oriented flange  55  at the periphery, so that the plate-shaped structure can be stored and transported with the flat upper surface  30  oriented mainly vertically, i.e. with the downwardly oriented flange  55   a,b  on a supporting storing and/or transporting structure. In the shown embodiment, the downwardly oriented flange  55   a,b  at the periphery are part of a cap structure  84  for clampingly receiving the upwardly extending exterior sidewall of the reservoir. The cap structure  84  has the shape of an inverted U-profile including a first edge portion  81  upwardly extending from the generally flat upper surface  30 , a generally flat top portion  82  adjacent to the first edge  81 , and a second edge portion  83  downwardly extending from the top portion  82 . Here, the second edge portion  83  is part of the downwardly oriented flange  55 . The generally flat top portion  82  of the cap structure  84  may have a mainly constant width. However, in a specific design, the width of the generally flat top portion may be position dependent. In the shown embodiment, said generally flat top portion has wider sections  55   c  at a central position along a side of the plate-shaped structure, thereby providing improved rigidity to the plate-shaped structure. Similar to the embodiment shown in  FIG. 1 , openings  56   a - c  are provided at the outer edge of the generally flat upper surface  30  for clamping the plate-shaped structure  1  to the reservoir  10 . Here, said openings  56   a - c  are provided in the downwardly oriented flange  55 . 
       FIG. 6 a    shows a perspective schematic view of a covering cap  76  positioned in an upper portion of the drain opening  35  of the plate-shaped structure shown in  FIGS. 4 and 5 . The covering cap  76  has a generally flat central portion and an outer contour  77  matching a cross sectional geometry and dimension at an upper portion of the downwardly tapered sidewall  45  of the drain opening  35 . In the shown embodiment, the covering cap  76  is generally disc-shaped. Further, the covering cap is provided with a notch  78  at its outer contour  77  for allowing fluid to pass the covering cap  76  from the generally flat surface  30  towards a lower part of the drain opening  35 . Alternatively or additionally, the covering cap  76  is provided with an opening allowing fluid to pass. 
       FIG. 6 b    shows a perspective schematic view of a cap  70  positioned in the drain opening  35  of the plate-shaped structure shown in  FIGS. 4 and 5 . The cap  70  has a generally flat central portion  71  and a downwardly corrugated edge portion  72  having an outer contour that is in conformity with a cross sectional geometry of the downwardly tapered sidewall  45  of the drain opening  35 . In the shown embodiment, the cross sectional geometry of the drain opening sidewall  45  is circular. Then, also the outer periphery of the cap  70  is circular, thereby optimizing sealing properties. 
     The downwardly corrugated edge portion  72  of the cap  70  is provided with a notch  73  so that moisture may flow through the drain opening  35  into the reservoir  10 . Additionally or alternatively, a single or a multiple number of openings are provided in the generally flat central portion  71  and/or in the corrugated edge portion  72  to enable moisture flow. 
       FIG. 7  shows a schematic cross sectional view of the drain opening  35  of the plate-shaped structure shown in  FIGS. 4 and 5 . The covering cap  76  such as a ball shaped cap is located at an upper portion  45  upwards of the drain opening sidewall  45 , adjacent to the generally flat upper surface  30 . In the shown embodiment, the covering cap  76  is locked by locking members  45   a  extending from the drain opening sidewall  45  radially inwardly into the opening. However, the covering cap  76  can be fixed in another manner, e.g. by clamping the covering cap  76  in the sidewall  45 . The sealing cap  70  is located at a lower portion  45  low of the drain opening sidewall  45 , but can, in principle, move upwardly and downwardly in a certain range in a direction D mainly parallel to a body axis of symmetry B of the drain opening  35 . The outer contour of the cap  71  is designed such that it matches a cross sectional geometry and dimension of the downwardly tapered sidewall  45  of the drain opening  35 , at the above-mentioned lower portion  45  low thereof, e.g. close to or at the lower end of the drain opening sidewall  45 . The cap  70  has a weight that is greater that the weight of an amount of water with the same volume of the cap, i.e. greater than one kilogram multiplied by the volume of the cap in cubic decimeters. Preferably, the weight is at least 1.1 larger and more preferably at least twice as large. Cap  70  comprises a material having a density that is higher than that of water, thus providing an downwardly oriented force when the cap  70  is submerged in water. Of course cap  70  may also comprise a hollow space, or a space filled with lighter material, as long as the overall weight is sufficient to prevent floating in water. 
     During use, the cap  70  slides downwardly in the drain opening  35  until the periphery contacts the sidewall of the drain opening  35 , at the sidewall lower portion  45  low, thereby nearly sealing the opening and minimizing moisture evaporation. Due to roughness of the edge of cap  70  and/or the sidewall surface part that are in contact with each other water can seep down between cap  70  and the sidewall surface part. By providing a notch or opening or channels in the surface of cap  70  and/or the sidewall surface, moisture flow may be enhanced. Preferably, a seepage rate of at least one 0.2, more preferably 0.5 and preferably liter per minute is provided for the structure. When the rainfall is so high that the water level W rises, above the cap, the cap remains substantially in position, lodged against the side wall. Excessive rainfall will flow off the structure once the water level rises above the drain opening. 
     By providing the cap  70 , the greatest area on the water is covered, keeping the greatest part of the opening area protected against evaporation. Further, by providing the covering cap  76 , a shadow is shed on the cap  70 , thereby even further reducing an evaporation process. The seepage along cap  70  allows moisture to enter the reservoir, e.g. during a rainy period, but on the other hand, seals the opening entirely or almost entirely during periods of drought, this way preventing loss of precious moisture in the reservoir. In addition, the covering cap  76  provides a further protection against evaporation. 
     It is noted that, in another embodiment, only the cap is applied in the drain opening, not the covering cap, e.g. in order to save assembling steps. 
     It is also noted that the cap and/or the covering cap may have another design. In  FIG. 7  as an example, the cap may be implemented as a clay ball. When the cap is implemented as a clay ball, it can be used without a notch or opening, thereby further reducing evaporation. The outer contour of the ball  71  is designed such that it matches a cross sectional geometry and dimension of the downwardly tapered sidewall  45  of the drain opening  35 , at the above-mentioned lower portion  45  thereof, e.g. close to or at the lower end of the sidewall  45  of the drain opening. 
       FIG. 8  shows an upper schematic perspective view of a third embodiment of a plate-shaped structure  1  for cultivating a plant according to the invention.  FIG. 9  shows a lower schematic perspective view of the plate-shaped structure  1 . Compared to the second embodiment shown in  FIGS. 4 and 5 , the location of the drain opening  35  has shifted, while a fourth cavity  37  has been realized at the previous location of the drain opening. 
       FIG. 10, 10A, 10B  show a schematic perspective view of a second embodiment of a reservoir according to the invention. Here, the exterior sidewall  11  of the reservoir  10  comprises outwardly extending protrusions  57   a - c,    58   a - c  for traversing corresponding openings  56   a - c  of the plate-shaped structure  1 . It is also noted that corresponding openings in the plate-shaped structure  1  can contain detents  570  that fix a protrusion  57   a,  for traversing corresponding openings  56   a  of the plate-shaped structure  1 . The detents  570  may be realized e.g. as an edge of the lower side of the opening  56  on the flange. Then, a lower edge may be formed by the detent  570  while an upper edge  571  of the opening  56  is formed by the generally flat top portion  82  of the inverted U-profile of the plate-shaped structure  1 , as described referring to  FIG. 4 . When the edge extends below a protrusion  57   a  on the reservoir it detains the protrusion  57   a.    
     In a specific embodiment, the opening  56   a  is provided in the generally flat top portion  82  and the second edge portion  83  extending downwardly from the top portion  82 . Further, the detent  570  may be folded back from the second edge portion  83  towards the first edge portion  81  of the inverted U-profile forming an inwardly staggered supporting element supporting the protrusion  57   a  that extends into the opening  56 . In a connected state of the plate-shaped structure and the reservoir  10 , the protrusion  57   a  is clamped, in a vertical direction, between the lower and upper edge of the opening  56 , i.e. between the detent  570  and upper edge  571 . The protrusion  57  functions as a tongue that is clamped between the lower and upper edge or lip of the opening  56 . Further, the protrusion  57   a  may also be locked in a horizontal direction, transverse to the vertical direction, viz. by the first edge portion  81  of the inverted U-profile on one side and by an inner edge interconnecting the top portion  82  and the second edge portion  83  of the inverted U-profile. Then, a reliable and firm connection between the plate-shaped structure  1  and the reservoir  10  is obtained having a further advantage of reduced evaporation of moisture that is present in the reservoir as the opening  56  is almost entirely closed by the protrusion  57   a.    
     In a highly preferred embodiment, the folded back detent  570  does not extend beyond or below the upper edge  571  of the opening  56  so that the plate-shaped structure can be made using a pulp moulding process. In the embodiment shown in  FIG. 10A , the fold back detent  570  maintains an offset D with respect to the upper edge  571  in a direction away from the second edge portion  83 . The fold back detent  570  leaves a volume V between the lower edge  570  and the upper edge  571 , the volume V having a width D in the plane P wherein the plate-shaped structure  1  extends. 
     Similarly, a detent may be realized by an edge of the lower side of an opening on the reservoir. When the edge extends above a protrusion on the flange it detains the protrusion. Alternatively or combined with this, the protrusions may be constructed in a similar way to form detents for detaining the protrusions in the openings. 
     In the embodiment shown in  FIG. 10B  a rim  110  is provided in the side wall of the reservoir (giving the side wall a step shaped cross-section) thereby reducing a risk that the straight sidewall collapses to the inside, caused by pressure from the soil outside the box. The rim  110  may be located substantially halfway between the bottom and the top of the reservoir. The rim  110  may extend along the entire circumference of the exterior sidewall  11 , however, as an alternative, an interrupted rim  110  along part of the circumference may be used. In the illustrated embodiment, the rim  110  is present selectively at each corner of the exterior sidewall  11  of a rectangular (preferably square) reservoir and in central sections between the corners. The exterior sidewall  11  may flanged twice outwardly, at its upper portion, forming an inverted U-shaped profile 
       FIG. 10C  shows an embodiment, comprising a further plate  120  in the reservoir, outer edges of the plate resting on the rim  110 . Such a plate  120  may be used to further reduce the risk of collapse of the side walls and/or the collection structure. Preferably, the further plate  120  has openings below the cavities to allow roots to pass. Preferably, these openings are so small that as least the edges of the cavities may be supported by the further plate and through them the collection structure. Preferably, the further plate has openings to allow water to pass. 
       FIG. 10D  shows a schematic perspective cross sectional view of a drain opening  35  provided in a fourth embodiment of a plate-shaped structure  1  according to the invention. The drain opening  35  has a sidewall  45  extending downwardly in a tapered manner for flowing moisture that is received on the generally flat upper surface  30  downwardly into the reservoir. In the shown embodiment, the drain opening  35  has no bottom portion. 
     Further, as shown in  FIG. 10E , the sidewall  45  of the drain opening  35  can be provided with slits  45   a  running downwardly to a lower edge  45   b  of the sidewall  45  so that a lower portion of the sidewall  45  can be moved radially outwardly, preferably temporarily, e.g. by pressing a tube, funnel or other foreign object into the drain opening  35 , thereby enlarging the opening so that a process of refilling the reservoir with water can be performed quickly. 
       FIG. 10E  shows a schematic perspective cross sectional view of a cavity  31  provided in the plate-shaped structure  1  of  FIG. 10D . The cavity  31  has a sidewall  41  tapered downwardly to a cavity bottom portion  51  that is provided with an aperture  61  to enable moisture communication between the interior of the cavity  31  and the inner space  80  of the reservoir  10 . The cavity bottom portion  51  is supported by the further plate  120  described referring to  FIG. 10C , preferably in a curved receiving portion  120   a  that is also provided with an aperture  120   b  aligned with the aperture  61  of the cavity bottom portion  51 . By using the further plate  120  to support the cavity bottom portion  120   a  a risk that the plate-shaped structure  1  collapses is further reduced. Optionally, the sidewall  41  of the cavity  31  can be provided with a single or a multiple number of slits  41   a  as shown in  FIG. 10E  to allow roots to grow also radially outwardly. Further, the cavity sidewall  41  can be provided with a cutting edge  41   d  that is preferably pre-cut or perforated so that a cavity sidewall  41  below said cutting edge  41   d  can be easily cut or torn off, e.g. for providing an opening  95  receiving a pot as shown in  FIG. 10G  below. 
       FIG. 10F  shows a schematic perspective cross sectional view of the plate-shaped structure  1  of  FIG. 10D  and a third embodiment of a reservoir  10  according to the invention in an assembled state. The plate-shaped structure  1  is provided with a funnel  90  that is received in the drain opening  35 . The funnel  90  preferably has a tapered sidewall  91  that has a similar geometry as the sidewall  45  of the drain opening  35 , for stability reasons. Further, the funnel  90  extends upwardly so that an upper edge  92  of the sidewall  91  is located above the generally flat upper surface  30  of the plate-shaped structure  1 . Then, the reservoir  10  can be refilled also if the reservoir is partially or completely buried in the soil. In the shown embodiment, a ball shaped cap  76  is located inside the sidewall  91  of the funnel  90  providing the siphon function described above. 
       FIG. 10G  shows a schematic perspective view of the assembled plate-shaped structure  1  and reservoir  10  of  FIG. 10F  wherein a number of pots are received on the plate-shaped structure  1 . Here, the cavities  31 - 31  have been removed thus forming openings  95  in the plate-shaped structure  1  supporting pots  96   a - c  having downwardly tapered sidewalls  97   a - c.  The pots  96  can be used for cultivating plant material such as seeds, seedlings, cuttings, rooted cuttings, plug plants, vegetables and/or pot plants. Preferably, the pots are provided with a single or a multiple number of openings in their bottom to enable moisture or vapour from the reservoir to penetrate the interior of the pots. 
       FIG. 10H  shows a schematic perspective view of the reservoir  10  of  FIG. 10F . The reservoir  10  is provided with a rim or rib  110  located substantially halfway between the bottom and the top of the reservoir. In the shown embodiment, the rim  110  runs along the entire circumference of the exterior sidewall  11 , thereby providing additional strength to the reservoir  10  reducing a risk of collapsing. In the shown embodiment, the side wall has an upper portion  11   a  and a lower portion  11   b  joined by the rim or rib  110 . The side wall upper portion  11   a  is staggered outwardly relative to the side wall lower portion  11   b.  It is noted that, alternatively, the upper portion  11   a  and the lower portion  11   b  are mutually aligned. Further, the exterior sidewall  11  in the embodiment shown in  FIG. 10H  extends upwardly towards a straight edge portion  11   c,  without an inverted U-shaped or other curved or folded profile. Additionally, the side wall  11  includes side wall portions  11   d  that are staggered inwardly and extend upwardly to a generally flat top portion element  11   e  extending transverse to the upwardly extending portion, and generally parallel to the generally flat upper surface  30  of the plate-shaped structure  1  to be connected to the reservoir  10 . The flat top portion element  11   e  preferably adjoins the straight edge portion  11   c.  Further, the flat top portion element  11   e  forms a protrusion  57  described above cooperating with a corresponding opening  56  such that it functions as a tongue that is clamped between the upper and lower edge or lip of the opening  56 . 
       FIG. 10I  shows a detailed schematic perspective view of the assembled plate-shaped structure  1  and reservoir  10  of  FIG. 10F . Again, the protrusion  57  functions as a tongue that is clamped between the lower and upper edge or lip  570 ;  571  of the opening  56 . 
       FIG. 10J  shows a schematic perspective view of the plate-shaped structure  1  of  FIG. 10D . As shown, the folded back detent  570  forming the lower edge or lip  570  does not extend beyond or below the upper edge or lip  571  of the opening  56 , leaving a volume between the lower edge  570  and the upper edge  571 , the volume having a width D in the plane P wherein the plate-shaped structure  1  extends. 
     Optionally, the reservoir  10  is provided with needle formed openings for irrigating moisture. 
     Preferably, the inverted U-shaped profile on the exterior sidewall  11  has a geometry that is similar to the cap structure  84  of the plate-shaped structure  1 , e.g. as shown in  FIG. 9 . In the shown embodiment, the upwardly extending sidewall  11  of the reservoir  10  includes an outwardly extending, generally flat top surface  55   e  and an edge portion  55   d  downwardly extending from the generally flat top surface  55   e.  The generally flat top surface  55   e  has a mainly constant width, but also has wider sections  55   f  at a central position along a side edge of the reservoir  10 , thereby providing improved rigidity to the plate-shaped structure. Then, the reservoir can be stored and transported with the flat bottom  14  oriented mainly vertically, i.e. with the downwardly oriented flange  55   d  on a supporting storing and/or transporting structure. The outwardly extending protrusions  57   a - c,    58   a - c  are provided on the edge portion  55   f  extending downwardly. During a process of assembling the reservoir  10  to a corresponding plate-shaped structure  1 , the inverted U-shaped profile on the exterior sidewall  11  of the reservoir  10  is received in the cap structure  84  of the plate-shaped structure, thereby obtaining a relatively stiff connection between the plate-shaped structure  1  and the reservoir  10 , in order to survive damaging natural forces such as wind, rain and weight of soil. The exterior dimensions of the inverted U-shaped profile of the reservoir  10  are slightly smaller than the interior dimensions of the cap structure  84  of the plate-shaped structure  1  to facilitate an easy and reliable fit when assembling the plate-shaped structure to the reservoir. Further, during the process of assembling, the outwardly extending protrusions  57   a - c,    58   a - c  are placed and oriented to traverse the corresponding openings  56   a - c  of the plate-shaped structure. 
       FIG. 11  shows a perspective schematic view of the plate-shaped structure  1  of  FIG. 4  and the reservoir  10  of  FIG. 10  in an assembled state, forming an autonomous unit. 
     The connection of the collection structure to the reservoir can be implemented using reversed U-profiles  55   d,e,f  as described above referring to  FIG. 10 . The upper side of the exterior sidewalls of the reservoir box has reversed U-profiles. The downside of the sides of the collection structure also has reversed U-profiles, but they are a little bigger, just so much that the reversed U-profiles of the sidewalls of the box fit in it. In the outer side of the reversed U-profile of the collection structure, there are openings and detents. In the outside of the reversed U-profile of the sidewall are ribs, also called protrusions, that fit through the openings and fix the detents. This way the collection cover is fixed well to the reservoir, also called box, and resistant against blowing off by strong winds, preventing sand and soil entering the reservoir with the wind, preventing water from the reservoir getting evaporated, and the reversed U-profiles in combination with the ribs on the side of the box prevent the sides of the reservoir and the sides of the interior side wall to collapse through the forces of water, soil and humidity. The reservoir can be square, rounded or rectangle in shape. 
       FIG. 12  shows a perspective schematic view of an assembled structure. The assembled structure  100  includes pre-constructed parts together forming an assembled structure having a square, rectangular, diamond, oval or rounded form, when seen from above. The assembled structure  100  is a combination of a multiple number of autonomous units shown in  FIG. 11  In the embodiment shown in  FIG. 12 , the assembled structure includes four autonomous units each having a plate-shaped structure  1   a - d  and a reservoir  10   a - d.  The individual autonomous units can be designed such that the assembled structure  100  includes a predefined number of such autonomous units, preferably using symmetry in the design of the assembled structure  100 . Generally, by designing square or rectangular shaped individual autonomous units, four autonomous units can be used to form a single assembled structure  100 . The assembled structure  100  preferably has a single central hole  34  bounded by an exterior sidewall section of each individual autonomous unit. In principle, each individual autonomous unit is formed by assembling a pre-constructed plate-shaped structure  1   a - d  to a corresponding reservoir  10   a - d,  as described above. Then, the individual autonomous units are combined in a single assembled structure  100  as e.g. shown in  FIG. 12 . The plate-shaped structures of the individual autonomous units include preferably at least one drain opening  35   a - d  for filling the individual reservoir, and optionally a single or a multiple number of cavities  31 . At least two individual autonomous units can be mainly identical. In the shown embodiment, the four individual autonomous units form each a quadrant of the plate-shaped structure. In a first variant, the individual autonomous units have a mainly equal size and structure, each plate-shaped structure having a drain opening  35  and a pre-selected number of cavities  31 . In a second variant, the individual autonomous units can be implemented differently, e.g. as two unit types, viz. a first unit type having a drain opening  35  and a single cavity and a second unit type having a drain opening  35  and two cavities. The individual autonomous units are assembled and put together preferably using a rope, strap, tie or elastic band  65  enclosing the downwardly oriented flanges  55  at the periphery of the plate-shaped structures  1   a - d.  Depending on the geometry and dimensions of the plate-shaped structures and corresponding reservoirs, also another number of individual autonomous units can be pre-constructed and assembled later, e.g. two autonomous units, three autonomous units, eight autonomous units or ten autonomous units. Then, relatively small molding machines may be used for the construction of relatively large assembled structures  100  including a single central hole  34 , thereby meeting specific local markets. 
     In order to get an optimum stacking of the product the innerside and outside side walls, the cavities, also called cones, the drain opening, also called inverted siphon, and the U-profiles may have a specified angle. The integrated inverted siphon leads to less evaporation of the water inside the reservoir. With a surface of approximately 90 cm 2  comparing to the approximately 1,500 cm 2  of the 38×38 cm reservoir  10 , comparing to the approximately 1,750 cm 2  of the 38×46 cm reservoir  10  and comparing to the approximately 2,400 cm 2  of the 38 and/or 57 cm diameter rounded model reservoir  10 , the inverted siphon may reduce the evaporation surface to respective approximately 6%, 5% and 7 and/or 2.75%. In the inverted siphon is a shell with a diameter that is approximately 6 to 10 mm less than the diameter of the inverted siphon. The model of the shell is like a plate with a cone in it, and with wings that go approximately 1 to 2 cm lower than the plate and then go horizontal again. In the middle of the cap a little space may be realized in a cone that is filled with air This gives the possibility to sow a seed in it or put a cutting through it. The sides of the inverted siphon hold the cap in a fixed way and being approximately 4 cm deeper in the inverted siphon, the wind cannot blow it away. The cap may have small spare openings that leave the moisture in when the collection structure captures it. 
     If instead a floating cap is used, the wings will be in the water when the cap floats. This prevents the cap from being blown away. The spare openings may help the water level to rise so that the cap can float again. The up and down moving cap closes the inverted siphon for almost 100% when the reservoir is full, and closes it for almost 100% when the reservoir&#39;s water level is lower, meaning, that we have a moving cap that goes up and down in a certain range from the top. This way a floating cap is provided, preventing the water from evaporating, while in the same time providing a possibility for moisture or water to enter when there is, and being fixed through intelligent wings floating in the water. 
     According to an aspect, the sidewall and/or the bottom of the reservoir can function as a slow release carrier for water. The permeability of the paper can be influenced through the concentration of substances that influence the permeability of paper. Generally, a higher concentration of the substances gives a lower permeability, and a lower concentration a higher permeability. The water permeability of the reservoir can also be set by selectively coating the sidewalls and the bottom with a coating layer. By selectively applying the coating layer the water permeability can locally be set. In an exemplary embodiment, a mask is used for spraying a coating material on the sidewalls and/or the bottom. Then, a part of the sidewalls and/or the bottom is coated while another part of the sidewalls and/or the bottom is not coated. In principle, the area of coated sidewall and/or bottom is highly water impermeable, while the area of uncoated sidewall and/or bottom is a direct measure for dosing the water permeability of the reservoir. As a further option, it is noted that the water permeability of the reservoir can be set by making micro-holes in the bottom and/or sidewall of the reservoir with one or more needles. The diameter of the needle, and the quantity of needles, also defines the watergift through these micro-holes. The micro-holes transport the water in the first weeks. During this period de cellulose absorbs some humidity and expands. After this period, the micro-holes may be closing. However, then the cellulose has absorbed the water and starts to add it to the soil below, through capillarity of the cellulose itself. It is noted that the above-mentioned options can be used in combination, e.g. the use of micro-holes in the bottom made with needles and the application of a location dependent coating layer. It is further noted that the irrigating capacity of the reservoir can also be set by a water release function through the use of one or more capillary cords. However, the adjustment of permeability and creating of micro-holes leads to the possibility of creating a reservoir that releases water without the use of a capillary cord, and with a speed of release that can be determined depending to the needs of the soil. In order for the user to be able to understand which permeability he needs, a reservoir for salted soils that has to release a high doses each day, can be made blue, a reservoir for sandy soils that has to release a lower doses can be made yellow, and a reservoir for clay soils that has to release the less water, can be made green. 
     The cellulose may degrade while using. For this reason it can function as a carrier for nutrients for the plants, as a carrier for substances that combat funguses, diseases and/or damaging animals. These substances can be mixed through the cellulose during the production process. As the circumstances are very dry, commonly used fertilizers and their applying method, cannot be used because of causing too high salt concentrations around the root system, leading to burning of the roots. The slow degradation of the cellulose, in combination with macro-elements N—P—K—Mg and micro-elements may lead to protection of the roots, to non-burning of the roots and a good and sufficient mineral availability absorbing situation even under dry circumstances. 
     For plants mycorrhizae form the carrier of minerals in the soil, to exchange them with. In order to have a higher mycorrhizae population it is interesting to inoculate the soil with desired species. During a process of producing the reservoir and/or the plate-shaped structure, the product may be heated after a moulding process, in order to dry it. For this reason it might be undesired or impossible to mix mycorrhizae through the cellulose during the production process. The drying process may sterilize the humid cellulose. For this reason the mycorrhizae may be added to the reservoir after the production process. This can be done by putting glue to the outside of the bottom and/or side of the reservoir and attach the mycorrhizae to this glue. Other glues from a chemical background may influence the life time of mycorrhizae. Some kill the mycorrhizae, other have an influence on the germination of seeds and the root development. Glue can be neutral to root development and seed germination. 
       FIG. 13  shows a perspective schematic view of an embodiment of the plate-shaped structure  1  with details of the flange  55  containing openings  56  and detents  570  for receiving protrusions. The plate-shaped structure  1  includes an inverted U-profile with a flat top surface  82  and a downwardly oriented flange  55  at the periphery of the generally flat top portion  82  wherein the downwardly oriented flange  55  comprises openings  56  for receiving protrusions. It is noted that protrusions can be, here and in general, a single protrusion generally extending along the perimeter of the reservoir or a number of individual protrusions. 
     The embodiment in  FIG. 13  comprises openings  56  provided in an edge area where the generally flat top portion  82  of the U-profile adjoins the flange  55  showing the openings are located partly on the generally flat top portion  82  and partly on the flange  55 . The openings are defined by a lower edge, two opposing side edges and an upper edge wherein the lower edge of the opening  56  may be the upper edge of an indent  570  in the flange of the plate-shaped structure  1 . The opposing side edges of the opening  56  may be positioned in the flange  55  and the upper edge of the opening  56  may be positioned in the generally flat top portion  82 . The upper edge of the opening  56  in the generally flat top portion  82  may be rounded, which is better in view of deformation stress distribution to prevent tearing. 
     Generally flat means in particular that at least the points at the perimeter of the surface that are in contact with the reservoir, in particular the top portion  82  of the inverted U-profile, are in one plane such as to fit closely to the upper edge of the reservoir. The term generally flat upper surface of the plate shape structure does not exclude presence of different shapes in the generally flat surface, as described above, for example drains, cavities, ridges, corrugations etc. In this particular embodiment of  FIG. 13 , the generally flat upper surface ( 30 ) of the plate shape structure comprises an outstanding protrusion comprising an opening for drinking and an indent so as to comfortably allow the lips of the drinker to enclose the drinking opening. This area may be rounded, may contain indented images or text, may be completely flat, may be hollow, may contain sharp edges or rounded edge, may be asymmetrical or any combinations of the above. 
       FIG. 14  shows a schematic side-view of the plate-shaped structure of  FIG. 13  wherein openings are provided extending in both the flange and the generally flat top portion  82  of the inverted u-profile for receiving protrusions and the flange comprises detents  570 . This embodiment shows openings  56  and detents  570  positioned so that a protrusion, for example a rolled-lip protrusion, can be received on the edge of the indent and provide a watertight clamp with the plate-shaped structure. 
       FIG. 15  shows a schematic top-view of the plate-shaped structure  1  of  FIG. 13  with details of the generally flat top portion  82  containing openings  56  and detents  570 . This view clearly shows the openings extend partly in the generally flat top portion of the inverted U profile. It is preferred that openings extend only over part of the substantially horizontal part of the inverted U-profile to provide a water tight connection with the reservoir. Clearly the opening should not extend inwardly beyond the inner wall of the reservoir. 
     In the particular embodiment of  FIG. 15 , the plate-shaped structure  1  comprises an opening for drinking and a geometry to allow for easier access to said opening. 
       FIG. 16  shows a cross-sectional view along the line indicated in  FIG. 15 , of the plate-shaped structure  1  of  FIG. 13  engaging a reservoir  10  with a rolled-lip protrusion  59 , detailing the flange  55  containing an opening  56  and a detent  570  for receiving said protrusion  59 , wherein a distance D between the edge  561  of the generally flat top part  82  of the inverted U profile and the edge of the indent  571  in a horizontal plane is defined. It is noted that the distance D allows easy removal of the plate shaped structure from the mould without deformation of the moulded article, which is particularly advantageous in case of paper pulp processing because fresh moulded paper pulp products are difficult to deform without tearing when removing them from the mould. Further, in view of easy removal from the mould in paper pulp processing the flange preferably has a flange angle of at least about 5, 7 or 10 degrees to a reference line perpendicular to the periphery of the generally flat surface. The invention allows to make a drinking cups and food reservoirs with covers that are fully biodegradable, preferably the cover being made from paper pulp and the reservoir being made from paper, preferably also from paper pulp. 
     The present disclosure allows the plate-shaped structure  1  to be manufactured using a pulp molding process, wherein the result of said process is a complete lid for covering a reservoir ( 1 ) wherein the process by which the plate-shaped structure  1  is produced may be a paper pulp molding thermo-forming process. The process of manufacturing the plate-shaped structure  1  may comprise two molds, a first mold and a contra-mold, wherein the geometry of the plate-shaped structure  1  allows the contra-mold to retrieve the plate-shaped structure  1  from the first mold without deformation of the plate-shaped structure  1 . The combination and geometry of the first mold and the contra-mold may limit the deposition of pulp for forming openings in the surface of the plate-shaped structure  1 . The limitation of deposition of pulp on certain places of the geometry allows openings to be formed in the surface area of the plate-shaped structure  1 . The placing of these openings allows the development of a plate-shaped structure  1  that holds a protrusion of a reservoir in place while simultaneously being easily extractable from the first mold. 
       FIG. 17  shows a schematic top-view close-up of the plate-shaped structure  1  of  FIG. 15  with details of the flange  55 , the generally flat top part of the inverted U profile  82 , the opening  56  and the detent  570 , wherein a distance D between the edge of the generally flat upper surface  561  and the edge of the indent  571  in a horizontal plane is defined.  FIG. 17  shows the shaded area as the thickness of the plate-shaped structure  1  on the location where the opening  56  is applied in the surface of the plate-shaped structure  1 . 
       FIG. 18  shows a schematic cross-sectional side view of an assembly of the plate-shaped structure  1  of  FIG. 13  and a reservoir  10 . In this particular embodiment, the reservoir  10  may be a cup, for example a drinking cup, releasably engaged with the plate-shaped structure  1  which is applied as a cover for said reservoir  10 . 
     The invention is not restricted to the embodiments described herein. It will be understood that many variants are possible. 
     It is noted that the top edge of the reservoir exterior side wall may mainly form a square contour. However, also other contours are possible, such as a rectangular contour or a polygon contour. 
     Further, instead of a single stay, a multiple number of stays can be used to define a predefined offset between opposite sections of the interior side wall top edge of the reservoir. 
     It is also noted that the central opening of the plate-shaped structure may support a sheath foil surrounding the plant. An exemplary sheath foil is described in the Dutch patent application 2012651 in the name of the applicant. 
     It is noted that the design of the drain opening and the cap can be applied in combination with the plate-shaped structure as defined in claim  1 , but also more generally in a plate-shaped structure for cultivating a plant, comprising an upper surface without a cavity. As an example, a plate-shaped structure for cultivating one or more plants can be provided with the above-mentioned drain opening and a cap, but without a cavity. 
     It is further noted that the design of the protrusions and the corresponding openings for assembling a reservoir and a plate-shaped structure for cultivating a plant according to claim  1  can be applied more generally to a reservoir and a plate-shaped structure for cultivating a plant, the structure comprising a generally flat upper surface without a cavity. 
     It is especially noted that the design of the protrusions and the corresponding openings for assembling can not only be applied to a reservoir and a plate-shaped structure for cultivating a plant, but also for connecting a cover to a cup such as a drinking cup, more especially if the cover and cup are manufactured from a pulp moulding process such as from cellulose and/or paper material. Then, the cup generally includes an upwardly extending exterior sidewall, and the cover covering the cup has a generally flat upper surface including a downwardly oriented flange at the peripheral of the generally flat upper surface, for receiving the upwardly extending exterior sidewall of the cup. The downwardly oriented flange and the upwardly extending exterior sidewall comprise corresponding protrusions and openings for receiving the protrusions. 
     Similarly, it is noted that the concept of providing a stay on the collection structure and/or the reservoir defining a predefined offset between opposite sections of the central opening can be applied to the plate-shaped structure as defined in claim  1 , but also more generally in a plate-shaped structure for cultivating a plant, comprising an upper surface without a cavity. 
     It also noted that the described concepts, such as the drain opening and the cap, the protrusions, the detents and the corresponding openings for assembling, the stay, the concept of assembling the plate-shaped structure and/or the reservoir from pre-constructed parts, the concept wherein a sidewall and/or a bottom of the reservoir functions as a slow release carrier for water, and the design of the cavity on the plate-shaped structure may be applied to plate-shaped structures or a reservoir respectively for cultivating a plant, but also to structures having another upper surface for cultivating a plant, e.g. a curved surface or a funnel-shaped surface, as described e.g. in patent publication WO 2009/078721. 
     As a further example of a variant, it is noted that the reservoir and/or the plate-shaped structure can be provided with stiffening elements such as horizontal, vertical and/or diagonal rim members to increase stiffness of the reservoir. 
     It is also noted that the assembled reservoir and plate-shaped structure can be put on the ground or can be buried in the ground, either partially or completely. Further, the assembled reservoir and plate-shaped structure can be applied in flat or sloped areas such as hills or mountains. Other such variants will be apparent for the person skilled in the art and are considered to fall within the scope of the invention as defined in the following claims. For the purpose of clarity and a concise description features are described herein as part of the same or separate embodiments. However, it will be appreciated that the scope of the invention may include embodiments having combinations of all or some of the features described. 
     The following numbered paragraphs set out particular combinations of features which are considered relevant to particular embodiments of the present disclosure.
     1. A plate-shaped structure designed for covering a reservoir, said plate-shaped structure comprises a substantially flat surface and a flange at the periphery of the substantially flat upper surface, wherein the flange comprises plurality of openings designed to receive a protrusion on an exterior sidewall of the reservoir, thereby covering the reservoir.   2. The plate-shaped structure of paragraph 1, wherein the flange contains a plurality of detents designed to releasably hold the protrusion on the exterior sidewall of the reservoir.   3. The plate-shaped structure of paragraph 1, wherein the openings are provided in an edge area where the generally flat upper surface adjoins the flange of the plate-shaped structure.   4. The plate-shaped structure of paragraph 1, wherein the flange of the plate-shaped structure includes an inwardly staggered supporting element forming a detent designed for detaining a protrusion of the reservoir in the opening.   5. The plate-shaped structure of paragraph 2 or 4, wherein the detent does not extend beyond the upper edge of the openings.   6. The plate-shaped structure of paragraph 5, wherein the detent leaves a volume between the detent and the upper edge of the opening, the volume having a width in the plane wherein the plate-shaped structure extends.   7. The plate-shaped structure of paragraph 1, wherein the flange is part of an inverted U-profile designed for receiving the upwardly extending exterior sidewall of the reservoir.   8. The plate-shaped structure of paragraph 7, wherein said openings comprise a lower edge and an upper edge and wherein detents form an edge of the lower side of the openings on the flange and the upper edge is on the generally flat top portion of the inverted U-profile of the plate-shaped structure.   9. The plate-shaped structure of paragraph 1, wherein the plate-shaped structure is manufactured from cellulose and/or paper material and/or plastic.   10. The plate-shaped structure of paragraph 1, wherein the plate-shaped structure is manufactured from biodegradable material selected from cellulose, paper material, biodegradable plastic or combinations thereof.   11. The plate-shaped structure of paragraph 1, wherein the plate-shaped structure is designed as a cover for a cup.   12. The plate-shaped structure of paragraph 1, wherein the plate-shaped structure is designed as a cover for a drinking cup.   13. The plate-shaped structure of paragraph 1, having a generally circular shape.   14. The plate-shaped structure of paragraph 1, having a substantially square or substantially rectangular shape.   15. The plate-shaped structure of paragraph 1, wherein the plate-shaped structure is designed as a cover for a reservoir wherein said reservoir is a food container.   16. The plate-shaped structure of paragraph 1, having at least 4 openings and detents.   17. The plate-shaped structure of paragraph 7, having openings extending partly in the substantially horizontal part of the inverted U-profile and partly in the flange and detents in the flange under the openings.   18. The plate-shaped structure of paragraph 17, wherein the openings extend only over part of the substantially horizontal part of the inverted U-profile to provide a water tight connection with the reservoir.   19. The plate-shaped structure of paragraph 1, wherein the flange has a flange angle of at least about 5, 7 or 10 degrees to a reference line perpendicular to the periphery of the generally flat surface.   20. An assembly comprising a reservoir comprising an upwardly extending exterior sidewall comprising one or more outwardly extending protrusion and a plate-shaped structure having a generally flat upper surface including a downwardly oriented flange at the periphery of the generally flat upper surface designed for receiving the upwardly extending exterior sidewall of the reservoir wherein the downwardly oriented flange comprises openings designed for receiving one or more protrusions on the upwardly extending exterior sidewall of the reservoir.   21. The assembly of paragraph 20, wherein the flange contains a plurality of detents designed to releasably hold the protrusion on the exterior sidewall of the reservoir.   22. The assembly of paragraph 20, wherein the openings are provided in an edge area where the generally flat upper surface adjoins the flange of the plate-shaped structure.   23. The assembly of paragraph 20, wherein the flange of the plate-shaped structure includes an inwardly staggered supporting element forming a detent designed for detaining a protrusion of the reservoir in the opening.   24. The assembly of paragraph 21 or 22, wherein the detent does not extend beyond the upper edge of the openings.   25. The assembly of paragraph 24, wherein the detent leaves a volume between the detent and the upper edge of the opening, the volume having a width in the plane wherein the plate-shaped structure extends.   26. The assembly of paragraph 20, wherein the flange is part of an inverted U-profile designed for receiving the upwardly extending exterior sidewall of the reservoir.   27. The assembly of paragraph 26, wherein said openings comprise a lower edge and an upper edge and wherein detents form an edge of the lower side of the openings on the flange and the upper edge is on the generally flat top portion of the inverted U-profile of the plate-shaped structure.   28 The assembly of paragraph 20, wherein the plate-shaped structure is manufactured from cellulose and/or paper material and/or plastic.   29. The assembly of paragraph 20, wherein the plate-shaped structure is manufactured from biodegradable material selected from cellulose, paper material, biodegradable plastic or combinations thereof   30. The assembly of paragraph 20, wherein the plate-shaped structure is designed as a cover for a cup.   31. The assembly of paragraph 20, wherein the plate-shaped structure is designed as a cover for a drinking cup.   32. The assembly of paragraph 20, having a generally circular shape.   33. The assembly of paragraph 20, having a substantially square or substantially rectangular shape.   34. The assembly of paragraph 20, wherein the plate-shaped structure is designed as a cover for a reservoir wherein said reservoir is a food container.   35. The assembly of paragraph 20, having at least 4 openings and detents.   36 The assembly of paragraph 26, having openings extending partly in the substantially horizontal part of the inverted U-profile and partly in the flange and detents in the flange under the openings.   37 The assembly of paragraph 17, wherein the openings extend only over part of the substantially horizontal part of the inverted U-profile to provide a water tight connection with the reservoir.   38. The assembly of paragraph 20, wherein the flange has a flange angle of at least about 5, 7 or 10 degrees to a reference line perpendicular to the periphery of the generally flat surface.   39. The assembly according to paragraph 20, wherein the reservoir is a drinking cup.   40. The assembly according to paragraph 20, wherein the protrusion on the reservoir is a tongue or a rolled-lip protrusion.   41. The assembly according to paragraph 20, wherein the protrusion on the reservoir is a rolled-lip protrusion along the circumference at the upper edge of the upward extending exterior side wall of the reservoir or a tongue.   42. The assembly according to paragraph 20, wherein the reservoir and the cover are manufactured from biodegradable material selected from cellulose, paper material, biodegradable plastic or combinations thereof.   43. The assembly according to paragraph 24, wherein the cover is manufactured from paper pulp.   44. The assembly according to paragraph 24, wherein both the cover and the cup are manufactured from paper pulp.   45. A process for the manufacture of the plate-shaped structure of paragraph 1-19, using a pulp molding process.   46. The process of paragraph 45, wherein the plate-shaped structure is manufactured using a paper pump molding thermo-forming process.   47. The process of paragraph 45, comprising a first mold and a contra-mold, wherein the geometry of the plate-shaped structure allows the contra-mold to retrieve the plate-shaped structure from the first mold without deformation of the plate-shaped structure.   48. The process of paragraph 47, wherein the first mold and the contra-mold in combination limit deposition of pulp for forming openings in the surface of the plate-shaped structure.