NURSERY POT MULCHING COLLAR

Abstract: A mulching cover (10a) for a nursery pot (P) includes an apron (12) for shielding the mouth (M) of the pot (P) and a flange (14) for connecting the apron (12) to the rim (R) of the pot (P), the apron (12) and the flange (14) being cleaved by a radial breach (24a) for receiving a plant stem. A perforated annular trough (16) circumscribes the perimeter of the apron (12) where it meets the flange (14), the trough (16) serving to retain and dispense any water and fertilizer intercepted by the apron (12). The flange (14) includes a series of ribs (18), preferably annular, for engaging the mouth (M) of the pot (P), particularly where the mouth (M) includes annular troughs as is common. The apron (12), the trough (16), and the flange (14) are resilient and together form a spring biased to open the breach (24a) and urge the cover (10a) against the mouth (M) of the pot (P) to hold the cover (10a) in place.

Description: NURSERY POT MULCHING COLLAR FIELD OF THE INVENTION The present invention relates to an agricultural device called a mulching collar and more specifically, to a mulching collar which can be attached as a lid to a pot or planter. BACKGROUND OF THE INVENTION Mulch is used in agriculture to inhibit weed growth and encourage crop growth. The simplest form of mulch is a layer of straw, leaves or wood chips spread on the soil around the desired plants. In more modern applications, dark plastic is often used, held down by soil, weights, or stakes . Mulch works by preventing light from reaching young weeds trying to germinate in the soil . The desired crop has its leaves above the mulch and gets full sunlight for photosynthesis while the weeds starve in the dark. This, of course, leaves more light, nutrients and water for the desired crops. Aside from this primary purpose, mulch provides the secondary benefits of moisture retention and heat retention. Mulch performs these functions by acting as a barrier, preventing air flow from stealing moisture from the soil through evaporation and from stealing heat from the soil through convection. At the same time, the mulch should permit some air flow to prevent mould and rot . Thus, a good mulch should provide a moderating influence, avoiding extremes of heat and moisture. Unlike a row of strawberries or a bed of flowers which can be mulched quickly and easily with straw or a sheet of plastic, plants in pots must be mulched one pot at a time. To use plastic sheeting, a nurseryman must: cut a circular piece of sheeting, slice a radial slot in the piece of sheeting to receive the plant, place the plastic around the plant stem and within the pot and spread dirt overtop to keep the mulching sheet in place. In a nursery setting, where hundreds or thousands of pots need mulching, this process would be unacceptably labour intensive. As well, erosion from watering would eventually wash the dirt from the plastic, leaving the plastic exposed to wind and sun to become ragged and ineffective. Attempts have been made to produce a mulch collar which could more easily be applied to nursery pots. United States patent number 3,961,443, granted on June 8, 1976 to Charles J. Insalaco for a, "Cover For Nursery Pots Providing Improved Protection, Support and Feeding, " describes such a mulch collar which is attached to the rim of the pot by means of a channel or "inverted U" which is cut around the edge of the collar and which locks onto the rim of the pot. This collar functions similarly to well known re-sealable kitchen container lids, the most famous being known by the trademark "TUPPER ARE . " As with "TUPPERWARE" , the Insalaco mulch collar channel must be carefully sealed around the entire perimeter of the pot, a time-consuming process when there are thousands of collars to install. Furthermore, the collar and the pot must have substantially similar diameters if they are to fit properly. Insalaco addressed this later problem by suggesting colour-coded pots be made specifically for his collars. However, the market reality in the nursery industry is that the pots must be cheap and generic. Insalaco' s collar suffers from another design problem in that the top of the collar slopes downwards towards its centre hole in a series of concentric terraces. This geometry directs applied water and fertilizer towards the plant at the centre, which could lead to over-fertilizing and the death of the plant . United States patent number 5,058,317, granted on October 22, 1991 to Lawrence J. McMurtrey for a, "Mulch Collar," describes a mulch collar which is made of soft, pliable plastic apron with a hole in the centre to pass a plant and a slit from the centre hole to the edge so that the hole can be opened to receive the plant . Around the perimeter of the apron is found a circular spring made of metal or plastic and which is welded or glued to the plastic apron. The spring has two ends which coincide with the two edges of the slit in the plastic apron, the spring serving to urge the slit closed. In operation, the user places one hand on each side of the slit and opens the slit, deforming the spring. With the slit open, the collar can be placed around the plant stem and the slit permitted to close under the influence of the spring. If the diameter of the collar is made to be slightly larger than the diameter of the pot opening, then the collar can be forced into the pot and the spring will be compressed by the pot. The spring exerts a force against the pot, the pot and spring forces serving to hold the collar in place. There are, however, problems with McMurtrey' s collar. Firstly, his collar requires a two-part construction, with a long weld or glue seam to hold the parts together. This design adds to the complexity and cost of the manufacturing process and yields a less robust collar than would one piece construction. With a nursery requiring several thousand lids, cost and durability are essential considerations . A second shortcoming is that the collar requires two hands to use, one on either side of the slit. This means that there is no hand available to steady the pot or steady the worker or to hold a stack of additional collars for use with other pots. Furthermore, it requires more time to install as the slit has to be forced opened and then closed around the plant . Lastly, the collar, when installed in the pot, is pushed down below the rim of the pot with nothing projecting above. Therefore, to remove the collar, the worker has to fish around and may require a screwdriver or knife to compress the spring and pry the collar out. It is likely that many collars would be damaged in removal, adding to the cost of using this system. What is needed is a cheap, simple mulch collar which can be quickly and easily attached to and detached from generic nursery pots. The collar should be durable and simple to manufacture. The collar should also resist over-fertilizing. The present invention is directed to such a device. SUMMARY OF THE INVENTION In accordance with one aspect of the inventin, there is provided a mulch collar that fits over a the mouth of a nursery pot. The collar has a perforated annular trough which retains applied fertilizer and water, releasing them slowly about the pot perimeter to prevent excessive fertilizing and watering. The collar also has a ribbed flange which together with the trough forms a spring. The spring force serves to hold the collar inside the pot, the exterior annular ribs on the flange engaging the interior annular ribs found on most nursery pots. The collar further includes an annular cap circumscribing the top of the flange, which engages the rim of the pot to limit the travel of the collar into the pot and which provides a handhold both for carrying the pot and for removing the collar. According to another aspect of the invention there is provided a cover for a nursery pot having a lipped mouth through which a plant may extend, the cover comprising: a sheet of thin material adapted to fit through the mouth to reside within the nursery pot, the sheet defining an aperture that aligns with the mouth when the sheet resides within the nursery pot, thereby permitting the plant to extend through both the mouth and the aperture, a flange adapted to engage the perimeter of the sheet and to extend outwardly therefrom at an obtuse angle to engage the lip of the nursery pot, and an annular trough at the junction between the sheet and the flange. The annular trough might be perforated to permit water or nutrients to pass therethrough and the sheet, the flange, and the trough might be unitary and resilient such that the sheet, the flange, and the trough form a spring. The exterior surface of the flange might define ribs adapted to engage the interior surface of the pot and the ribs might be annular, perhaps as a result of flange being corrugated. The sheet, the flange, and the trough might define a first radial breach extending from the aperture and the first radial breach might be biased open. Furthermore, the sheet might define a second radial breach extending from the aperture, and the second radial breach might be biased closed. It is also anticipated that the sheet in the region of the aperture might be biased away from the plane defined by the rest of the sheet. BRIEF DESCRIPTION OF THE DRAWINGS These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description, appended claims, and accompanying drawings where : Figure 1 is a perspective view of a mulching collar according to a first embodiment of the invention; Figure 2 is an elevational section view of the mulching collar of Figure 1 taken along the line A-A; Figure 3 is a perspective view of a mulching collar according to a second embodiment of the invention; and Figure 4 is an elevational section view of a mulching collar according to a third embodiment of the invention. DETAILED DESCRIPTION With reference now to Figures 1 and 2, a mulching collar for use in a nursery pot P (not part of the invention) and the like is generally illustrated at 10. The mulching collar 10 has a depressed shape like a bowl and may made from plastic, aluminium foil or any other opaque material having suitable resiliency and stiffness to produce the behaviour described herein. The collar 10 includes a substantially horizontal apron 12 and a substantially vertical flange 14 extending from the perimeter of the apron at an obtuse angle. Preferably the apron 12 and flange 14 form an integral and unitary whole that is cheap to manufacture and durable; however, it is anticipated that the apron 12 and flange 14 might also be separately formed and then fastened or bonded together by various well known means. The apron 12 is shaped to fit within the mouth M of the pot P, retained in place by the flange 14 which is shaped to engage the pot P mouth M. Around the perimeter of the apron 12 is further characterized by an annular trough 16 which is perforated at intervals along its length. The trough is formed to catch and hold both fertilizer and water deposited onto the apron 12 and to release them slowly about the perimeter of the pot through the perforations, thereby resisting over-fertilizing and soil erosion. The perforations also provide a path for airflow between the atmosphere and the interior of the pot P, thereby reducing the risk of mould and mildew. Alternatively, it is envisioned that the annular trough 16 might remain unperforated to catch and hold both fertilizer and water but to dispense only the excess that spills over the bank of the trough 16, the remainder evaporating or eroding away. The substantially vertical flange 14 is ringed by a series of horizontal ribs 18. Each annular rib 18 might be continuous or discontinuous. The annular ribs 18 serve to stiffen the flange 14, improving its ability to function as a spring. The annular ribs 18 also texture the outside surface of the flange 14, helping to hold the collar in place against the planter P mouth M as will be further explained below. The annular ribs 18 may be formed as protrusions or may result from the corrugation 18, 18' of the flange 14. In place of the annular ribs 18, one might include instead vertical ribs, dimples, knurling, or the like; however, while such textures would help to engage the pot P mouth M, they would be unlikely to aid the spring function of the flange 14 to the same extent as the annular ribs 18. The flange 14 is topped by an annular cap 20 which forms in cross-section an inverted "U" . This cap 20 limits how far the collar 10 can be inserted into the pot by catching on the upper rim R of the pot P. The cap 20 also serves as a convenient finger hold for inserting or removing the collar 10 and for grabbing the pot P by its rim R. The flange 14 gives the collar 10 a tapered profile, conveniently like a bung. The bottom of the collar 10 (the apron 12) is narrow and fits easily into the pot P. However, the top of the collar 10 is broader than the mouth M of the pot P and therefore sprung, flaring flange 14 must be compressed before the upper portion of the collar 12 could fit within the pot P mouth M. In this first embodiment of the collar 10, an iris-shaped aperture generally illustrated at 22 pierces the apron 12. The iris-shaped aperture 22 is defined by a wide substantially radial channel 24 which breaches the apron 12 from its center 26 through the trough 16 and the flange 14 and by one or more narrower substantially radial slits 28 which slice through the apron 12 to its centre 26 but terminate well short of the perimeter of the collar 10 before the inside edge of the annular trough 16. The radial channel 24 is normally open and is wide enough in that state to receive a plant stem S. The radial channel 24 and the radial slits 28 divide the apron 12 into approximately equal sized iris petals 30 and facilitate resilient bending of the collar 10 at the apron 12, the ribbed flange 14, and the annular trough 16. The iris petals 30 may be biased upwards or downwards away from the plane of the rest of the apron 12 both to facilitate spring deformation and to present a safe, smooth, flat surface to the plant stem S . An apparatus according to a second embodiment of the invention is generally illustrated at 10a in Figure 3. The second embodiment mulch collar 10a is very similar to the first embodiment mulch collar 10 differing in that a central aperture 22a punctures the apron 12 and a substantially radial channel 24a breaches the apron 12 from the central aperture 22a to the outer edge of the flange 14. This simpler second embodiment allows the collar 10a to receive a plant stem S within the central aperture 22a through the radial channel 24a but has reduced springiness compared to the first embodiment because there are no secondary radial slits to facilitate the deformation of the collar 10a. In the collar's 10, 10a normal unstressed state, the channel 24, 24a is open and the spring is uncompressed. -In this state, the plant stem S can be received withi ' n the channel 24, 24a and the collar 10, 10a can easily be placed around the plant stem S. As the collar 10, 10a is inserted into the mouth M of the pot P, the mouth M compresses the sprung, flaring, flange 14, the outer surface of the flange 14 being stretched (tensioned) , the inner surface of the trough 16 being compressed, and the apron 12 being deformed toward or away from the pot P, all resulting in the development of a spring force which resists further compression of the collar 10. When the collar 10 is compressed sufficiently to fit completely within in the pot P mouth M, the user can release the collar 10 and the cap 20 will engage the rim R of the pot P. The collar 10 spring force will be exerted against the pot P, forcing the ribs 18 on the flange 14 into the annular troughs T found on the interior of most nursery pots. The ribbed flange 14 depressed within the pot P mouth M presents a convenient surface for a nurseryman to grab onto the pot P for carrying. To remove the collar 10, the user merely grabs the cap 20 with one hand and lifts the collar 10 out of the pot P. The collar 10 spring force and the tapered shape of the flange 14 combine with the nurseryman's lifting force to pop the collar 10 out of the pot P, the collar 10 spring force forcing the radial channel 24 open to permit the collar 10 to be removed from around the plant stem S. Referring to Figure 4 an apparatus according to a third embodiment of the invention is shown generally at 100. The apparatus is similar to the apparatus shown in Figure 2, with the exception that it does not include the annular cap 20 shown in Figure 2 but rather includes a flat planar annular ring 102. The rim contacts the inner wall of the pot, allowing the collar 10 to be inserted into the pot more deeply than shown in Figure 2, until the walls of the pot interfere with the annular ring to the point where the collar can be pressed no further into the pot. While the above apparatus provides advantages when used with conventional nursery pots, it may also be used with pots used to hold water plants. This is particularly advantageous where the water plants are disposed in a pool holding koi fish which often damage the roots of such plants. The apparatus covers the roots of water plants, thereby protecting the roots from fish. Although a specific embodiment of the present invention has been described and illustrated, the present invention is not limited to the features of this embodiment, but includes all variations and modifications within the scope of the claims.

Claims: CLAIMS 1. A cover for a nursery pot having a lipped mouth through which a plant may extend, the cover comprising: a. a sheet of thin material adapted to fit through the mouth to reside within the nursery pot, the sheet defining an aperture that aligns with the mouth when the sheet resides within the nursery pot, thereby permitting the plant to extend through both the mouth and the aperture, b. a flange adapted to engage the perimeter of the sheet and to extend outwardly therefrom at an obtuse angle; and c. an annular trough at the junction between the sheet and the flange. 2. A cover as in Claim 1 wherein the annular trough is perforated to permit water or nutrients to pass therethrough . 3. A cover as in Claim 2 wherein the sheet, the flange, and the trough are unitary. 4. A cover as in Claim 2 wherein the sheet, the flange, and the trough are resilient. 5. A cover as in Claim 4 wherein the sheet, the flange, and the trough form a spring. 6. A cover as in Claim 5 wherein the exterior surface of the flange defines ribs adapted to engage the interior surface of the pot . 7. A cover as in Claim 6 wherein the ribs are annular. 8. A cover as in Claim 7 wherein the flange is corrugated. 9. A cover as in Claim 8 wherein the sheet, the flange, - and the trough define a first radial breach extending from the aperture . 10. A cover as in Claim 9, wherein the first radial breach is biased open. 11. A cover as in Claim 10 wherein the sheet defines a second radial breach extending from the aperture. 12. A cover as in Claim 11, wherein the second radial breach is biased closed. 13. A cover as in Claim 12 wherein the sheet in the region of the aperture is biased away from the plane defined by the rest of the sheet . 14. A cover as in Claim 1 wherein said flange includes an annular cap for engaging the lipped mouth of the nursery pot.

Inventors: SCHOLTENS MICHAEL, SCHOLTENS, MICHAEL
Applicants: SCHOLTENS MICHAEL, SCHOLTENS, MICHAEL
Application year: 1998
Main classification: A01G13
IPC codes: A01G13