Abstract:
An apparatus and method for controlling apical growth of plants without cutting or pinching so as to increase productivity and efficiently utilize growth resources. A spring-shaped frame is provided having the form of mirror image/opposed Fibonacci or Golden Spirals that expand from a first starting point and then contract back to a second starting point by an approximately similar number of quarter-turns, the spring suitably being formed of a single length of wire. The apical growth tip of the plant is bent to meet the frame at selected locations and attached progressively as growth proceeds, using ties or other connectors. A stake inserted through the starting points of the spiral attaches the frame to the medium in which the plant is rooted. The stake is preferably angled so that the plant maximizes utilization of available light, for example, approximately 80° to the surface of the medium.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/176,378 filed on Feb. 13, 2015. 
     
    
     BACKGROUND 
       [0002]    a. Field of the Invention 
         [0003]    The present invention relates generally to frames and similar structures that support growing plants, and, more particularly, to a spring-shaped frame that trains the plant in a manner that allows control of apical dominance to be achieved in an efficient, cost-effective and low stress manner. 
         [0004]    b. Related Art 
         [0005]    Farmers and gardeners look for ways of increasing conditions and improving quality in their plants. Providing a plant with optimum environmental (e.g., water, light, soil/medium, CO 2 ) and nutritional support can go a long way towards achieving these goals. Beyond meeting a plant&#39;s environmental and nutritional needs, gardeners also often explore and employ methods of training to take a plant&#39;s yield and quality to a higher level. Certain fast growing plants, such as tomatoes for example, can benefit from increased branching. Also it can be advantageous to have evenly proportioned branches, as compared to apical dominance. Apical dominance refers to the process wherein the axillary buds (side or lateral shoots) remain dormant and are reserved by the auxin (plant hormone) that is produced by the apical shoot. When a plant&#39;s apical shoot is left intact and unbent the plant tends to take on a conical shape much like a Christmas tree, which is unsatisfactory for production of many vegetables and other crops. 
         [0006]    Removing apical dominance is achieved by either cutting (also referred to as pinching, pruning, topping and heading off) or bending of the plant&#39;s apical shoot. Cutting or bending the apical shoot removes the auxin&#39;s inhibitory effect on the axillary shoots so that growth of the latter is enhanced. Depending on the desired size of plant, and in order to distribute hormones and resources as evenly as possible among the branches/shoots, further pinching or bending may be necessary. This results in an increased number of equally proportioned branches and aids in training the plant for improved quality and increased yield. The shape of a plant trained in this manner is often that of an inverted cone. 
         [0007]    Removing growing shoots by cutting and pinching is perhaps the least time consuming method of training plants commonly employed by growers. Gardeners often use a form of shears to remove a growing tip (some may use only their hands and/or finger nails for smaller shoots). However, there are significant drawbacks to cutting a stem or stalk of a plant. First, an open wound left behind where cutting took place, leaving a plant exposed to infection or disease until the wound is healed. Second, growth vigor is lost while the plant repairs the injury and redirects growth hormone to other shoots/branches. In combination this results in lost time and growth opportunity during healing and redistribution of growth/hormone, which in turn may reduce yield and quality (if dealing with natural growing seasons), or may increase the time to harvest (if climate and environmental controls are in effect). As an additional drawback, auxins are transported down the stem to the roots; loss of auxin, due to removing an apical shoot, may result in less stimulated root growth and root branching. 
         [0008]    An alternative to pinching/cutting is bending. This can take various forms, from simply folding a growth shoot over, to attaching it to stakes trellis, netting or wires (e.g., an espalier), wrapping and bending with wire (e.g. bonsai), pulling it down and applying hanging weights, tying it down with cordage and stakes, and so on. After a growth shoot is bent it will immediately begin turning itself vertical again due to the effect of gravitropism (plant shoots display negative gravitropism; when placed on its side, a plant shoot will grow up against gravity) and will soon require further bending. Bending is advantageous relative to cutting in that it does not create an open wound and no auxin is lost. The main drawback of bending is that when using conventional techniques it is often much more time-consuming than cutting. This is a particular problem in commercial operations dealing with large numbers of relatively fast-growing plants, where the labor intensive aspects of conventional bending approaches become greatly compounded. 
         [0009]    Commercial growers also often use artificial lighting, in whole or in part, to expedite growth as compared with the natural growing season, and the cost of electricity creates the need to use the artificial light efficiently. Reducing the amount of time and electricity to produce crops requires that plants not be subjected to cutting for controlling apical dominance, in order to retain auxin and shorten the time from seed to harvest. Being able to adjust the orientation/angle of the plants may also help maximize utilization of light sources. Furthermore, for a variety of reasons pots or other containers are conventionally used to grow plants in commercial environments, and in order for a training technique/device to be most useful it is desirable that the containers remain individually mobile, rather being attached to trellises or other structures that interconnect plants such that they and their containers are not easily moved about. 
         [0010]    Thus, while prior methods of pruning and training are effective in increasing the number of evenly proportioned branches and therefore productivity, the drawbacks/limitations that are inherent to such methods leave a significant void when it comes to overcoming apical dominance in a rapid and efficient manner. 
         [0011]    Therefore, a need exists for a method and apparatus that overcomes apical dominance while reducing the amount of stress placed on the plant from training. Furthermore, there exists a need for such a method and apparatus that is easy to learn and that can be implemented in a rapid and efficient manner, especially when working with multiple plants. Still further, there exists a need for such a method and apparatus that facilitates efficient and economical use of lighting and other growing resources. Still further, there exists a need for such a method and apparatus that may be implemented using structural components that are economical to manufacture and transport, and that are adequately durable and long-lasting to permit reuse if desired. 
       SUMMARY OF THE INVENTION 
       [0012]    The present invention addresses the needs noted above, and concerns the growing and training of climbing, vining, branching, flowering, and fruiting plants, such as tomatoes or other vegetables or fruits, for example. 
         [0013]    The invention controls apical dominance and achieves a number of relatively evenly proportioned branches/growing shoots, without the drawbacks of cutting/pinching and without the labor-intensive and time-consuming aspects of conventional bending practices. The structure employed is mobile and if desired can be set up in an individual pot or other container so plants may be moved about as needed or desired. Apical shoots are not cut off, so auxin is not lost and growth vigor is maintained, resulting in shortened time frames from seed to harvest and minimization of resource consumption and days/hours of labor. In a preferred embodiment the invention is self-guiding/instructing in design and is therefore easily learned and implemented in small- or large-scale applications. 
         [0014]    In a first aspect the invention provides a spring-shaped frame, suitably formed of wire, referred to from time to time herein as simply a “spring.” The spring may take the shape of a Fibonacci or Golden Spiral that expands from a first center/starting point for a determined number of quarter turns, from which point the spring may contract by a similar number of quarter turns to a second center point so as to create two substantially symmetrical mirrored/opposed Golden Spirals. Preferably, the entire spring, including both Golden Spirals, may be formed of a single length of wire. A pitch may be applied to the spirals, for example by elevating one of the center points while the other remains fixed. Both the pitch and number of quarter turns the spirals make may be increased or decreased to accommodate various applications, uses and types of plants. 
         [0015]    Depending dimensions and use of the spring, attachment portions may be applied to the center point of each spiral that permit the spring to be attached to a stake or pole member that is inserted through both center points and into the soil or medium below. The attachment points may be continuations of the wire spring, and may be angled out from both the bottom and top spiral center points. The stake may be oriented at a selected angle to the soil line, for example, by an angle of approximately 80° off the soil line in a preferred embodiment. The proximity of the spring to the soil line may be adjusted by sliding the spring up or down the angled stake; once the desired position is reached, the attachment points may be secured to the angled stake, using cable ties or other connectors, for example. The angled stake may be supported by a second stake by positioning a second slake to meet with the top of the angled stake so that the arrangement results in a triangle, with the stakes making up two sides and the soil line the third. 
         [0016]    The present invention also provides a method for enhanced production from plants using controlled apical growth. In one aspect, a young plant may be positioned in the soil/medium near the center point of the spring closest to the soil/medium line and the plant allowed to grow vertically until its apical growth tip is above where it is to be attached to the spring frame as described above. Since bending the very tip of a growth shoot could result in snapping or splitting of the stem, it is preferable to bend further down the stem where tissues are more durable and hardened. At the point where the stem is sufficiently durable and in the proper position, a movement it may be made to bend the plant and the tip is then attached to the spring, using clips, twist ties or other connectors, for example. After the bend is made the plant may be left alone for a period of time so as to allow the plant to reorient to the new position and harden before bending again. As the growth rate of the plant increases, the wait time between bends may be reduced. The original apical shoot may be tied back down to the spring again and again while the axillary shoots are exposed to the light and their growth is thereby enhanced. Training to the spring may be continued until the plant has the desired number of shoots and the original apical shoot may then be allowed to grow vertically for the remainder of the plant&#39;s life cycle. 
         [0017]    These and other features and advantages of the present invention will be more fully appreciated form a reading of the following detailed description in connection with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]      FIG. 1  is a schematic representation of an example Fibonacci spiral, namely, an approximation of the Golden Spiral created by drawing circular arcs connecting the opposite corners of squares in the Fibonacci tiling, the example in  FIG. 1  using squares of sizes  1 , 1 , 2 , 3 , 5 , 8 , 13 , 21  and  34 ; 
           [0019]      FIG. 2  is a schematic view of two example Fibonacci spirals arranged in mirrored positions with points placed along the arcs of the spirals lettered from A-I, the lettered points being used for reference in  FIGS. 3 and 4 ; 
           [0020]      FIG. 3  is a schematic view of the two example Fibonacci spirals without tiling squares, and with lettered points for reference, the spirals being continuous and having arrows to show the direction of spiral expansion and spiral contraction, the arrows also being used for reference with respect to  FIG. 4  where a pitch is applied to the spirals; 
           [0021]      FIG. 4  is a side schematic view of expanding and contracting Fibonacci spirals having an example 30° pitch, with lettered points and arrows corresponding to  FIG. 2  and  FIG. 3 ; 
           [0022]      FIG. 5  is a side view of a spring-shaped frame in accordance with the present invention, having a pitched Fibonacci spiral configuration that correlates to that of  FIGS. 2-4 , with the lettered points and arrows having been removed and with stakes connected to attachment points at each end of the spring-shaped frame; 
           [0023]      FIG. 6  is a front perspective view of the spring-shaped frame of  FIG. 5 , attached to an angled stake, supported by an additional stake and set in a pot with soil and no plant; 
           [0024]      FIG. 7  is a side perspective view of the spring-shaped frame of  FIG. 5 , attached to an angled stake, supported by an additional stake and set in a pot with soil and no plant; 
           [0025]      FIG. 8  is a top plan view of the spring-shaped frame of  FIG. 5 , attached to an angled stake and set in a pot with soil and no plant; 
           [0026]      FIG. 9  is an enlarged perspective view of the spring-shaped frame of  FIG. 5 , showing the lower attachment point in greater detail; 
           [0027]      FIG. 10  is a second enlarged perspective view of the spring-shaped frame of  FIG. 5 , showing in greater detail the upper attachment point and the joint formed by the angled stake and support stake; 
           [0028]      FIG. 11  is a perspective view of the spring-shaped frame of  FIG. 5  attached to an angled stake and supported by an additional stake, and set in a pot with soil together with a plant; 
           [0029]      FIGS. 12-15  are perspective views of the spring-shaped frame of  FIG. 5 , attached to an angled stake and supported by an additional stake, and set in a pot with soil and a plant attached thereto and growing up the frame; 
           [0030]      FIG. 16  is an enlarged perspective view of the spring shaped frame of  FIG. 5  attached to an angled stake, showing in greater detail the first attachment of the plant to the spring shaped frame; and. 
           [0031]      FIG. 17  is an enlarged perspective view of a plant attached to and growing up the spring-shaped frame of  FIG. 5 . 
       
    
    
     DETAILED DESCRIPTION 
       [0032]    In nature growth frequently occurs in geometrically proportionate ways or patterns. These growth patterns have been linked to a mathematical expression referred to as Fibonacci Sequence or Golden Ratio. As shown in  FIG. 1  Fibonacci Sequence 10  ( 1 , 1 , 2 , 3 , 5 , 8 , 13 , 21 , 34 ) squares  14  and Spiral  12  grow at a rate similar to that of PHI 1.618 for each quarter turn from the center point  20 . The Fibonacci Spiral and the Golden Spiral are very close approximations of one another and are considered equivalents for purposes of the present invention. 
         [0033]    These natural growth patterns are often expressed in the spiral shape, for example, as seen in the nautilus shell, snail shell, fern, arrangement of sunflower seeds on a sunflower, and so on, a spiral being a curve on a plane that winds around a fixed center point at a continuously increasing distance from the center point. In natural growth of plants there is no simpler law than this, namely that it shall widen and lengthen in the same unvarying proportions. 
         [0034]    It has been found, through the use of the present invention, that by applying the Fibonacci Spiral to a wire, which is then pitched to a desired degree to form a double-spiral spring-shaped support as shown in  FIG. 4 , an effective means of overcoming apical dominance without removal of the apical shoot is provided. Furthermore, the arc  15  of the spring  38  opens up the plant in accordance with natural growth patterns and increases exposure to axillary shoots  58  and leaves. As the plant grows larger the Fibonacci Spiral continues to open up, increasing space for more and larger leaves, stems and shoots. The pitch applied to the arc  15  of the spring  38  provides control in overcoming apical dominance. Thus the desired pitch of the spring  38  relates to independent growth behaviors/patterns of various plant type (e.g. slow growing plants may prefer a lower pitch and fast growing plants a higher pitch). When the appropriate pitch is applied to the Fibonacci. Spiral for the plant being grown upon it, a harmonizing of growth is found. That is, the apical growth tip  54  and the axillary shoots  58  find an even pace of vertical growth  64  that continues to increase the number of evenly proportioned shoots/branches as long as the apical growth tip  54  is continually attached back to the spring  38 . This technique can for purposes of the present invention be referred to as “Apical Tuning” or “Tuning the Apex”. Once the desired plant size is achieved, bending may be discontinued and the apical growth tip  54  is allowed to continue vertically. 
         [0035]      FIG. 2  shows two Fibonacci Spirals in a mirrored position  13  with tiling squares. This arrangement of the Fibonacci Spirals provides the mathematical basis for the dimensions for the spring-shaped frame  38  whether scaled up or down in size. Points A-I  16  are points of reference to be used in  FIG. 3  and  FIG. 4 . 
         [0036]      FIG. 3  shows the Fibonacci Spirals with the tiling squares removed. The arrows  18  show the direction of the spirals&#39; expansion and contraction and that they are continuous from center point  20  to center point  22 . 
         [0037]      FIG. 4  shows a side view of the Fibonacci Spirals with a pitch applied. The arrows  18  show the direction of spiral expansion and contraction. Beginning with the lower center point  20  the Fibonacci Spiral  26  expands until it crosses the center line  24  at point E  16   a.  The Fibonacci Spiral  28  then contracts the same or approximately the same number of turns before ending at the upper center point  22 . The pitch applied in the example in  FIG. 4  is 30° or 33%, though other pitches may be applied, depending for example on the type of plant. It should be noted that  FIG. 4  is 2-dimensional and therefore does not describe the depth of the spirals&#39; arcs  15 , shortening the distance between points A-I  16 , having the effect of increasing the appearance of the applied pitch. 
         [0038]    In accordance with an exemplary embodiment of the present invention,  FIG. 5  shows a spring-shaped frame  38 . As shown, the spring-shaped frame  38  includes upper and lower Fibonacci Spiral portions  26  and  28  that correspond to the configuration of the Fibonacci segments shown back in  FIG. 4 . The frame  38  is suitably constructed of bent wire, though other materials may be used, such as extruded plastic, composites, wood, bamboo, or tubing, for example. Furthermore, while the frame may be in the form of a self-supporting coil as shown, it will be understood that some embodiments may include spokes, struts, webs, and other forms of internal and/or external structure as well. 
         [0039]    In  FIG. 5  The spring-shaped frame  38  is shown attached to an angled support stake or rod  30  that parallels/passes alongside the attachment points  32 ,  34  at each end. The stake  30  is preferably angled between 1-89° with respect to vertical as indicated by the vertical axis  24 , with an angle of about 80° being preferred to maximize utilization of light resources in many applications. The second stake  36  extends from the soil  52  generally vertically and meets at  40  the apex of the angled stake  30 . Using a cable tie  44  or other connector a joint is formed at the point  40  where the second stake  36  and the angled stake  30  meet, thus forming a triangular shaped configuration  42  that provides stability and ease of use. 
         [0040]    In accordance with a method of the present invention a plant  46  may be trained to spring  38  as follows. As can be seen in  FIG. 11  a young plant is first planted in the soil or other medium. Before any training is applied a period of time is allowed to pass so that the plant  46  may become established and begin to expand its roots into the newly available soil/medium  52 , in its new location/pot  48 . However, setup of the spring  38  may be done at this point rather than later, which will reduce the possibility of driving a stake through the newly formed roots. The angled stake  30  is set into the soil  52  so the spring  38  will be positioned in a manner that the spring  38  and plant  46  will intersect as the plant  46  grows vertical. It is preferable to have this intersection between plant  46  and spring  38  take place as close to the soil line  50  as possible, and also as close to the center point  20  of the base of the spring  38  as possible. In so doing, care should be exercised that the stake  30  is not inserted into the root ball in order to avoid injuring the young plant  46 . The spring  38  may be slid down the angled stake  30  by guiding the stake  30  through the bottom and top center points  20  and  22  of the spring  38  until the preferred distance between the soil line  50  and the bottom center point  20  of the spring  38  is reached. The spring  38  is rotated around the stake  30  until the pitch of the spring  38  is in proper relationship to the soil line  50 . For example; if the pitch of the spring  38  is set at 30° then it is attached to the stake  30  so that the 30° pitch is maintained in relation to the soil line  50 . 
         [0041]    The spring  38  is then attached, using cable ties or other connectors  44 , to the angled stake  30  by way of the attachment portions  32  and  34  located at the top and bottom center points  20  and  22 . In the illustrated embodiment the attachment portions  32  and  34  are a continuation of the spring  38  using the same material, although separate pieces may be employed in some instances. The attachment portions  32  and  34  are angled out the top and bottom center points  20  and  22  and aligned with the angled stake  30  for accessibility, attachment and removal. The second stake  36  is positioned in the soil  52  at or near vertical and so the uppermost portion of the stake  36  intersects  40  with the uppermost portion of the angled stake  30 . The second stake  36  stabilizes the position of the angled stake  30  and the spring  38 . Before attaching the second stake  36  to the angled stake  30 , check for proper positioning of the pitch of the spring in relation to the soil line  50 . 
         [0042]    After the plant  46  has begun to establish new roots and shoots an assessment of the plant&#39;s  46  readiness for bending is conducted. First the apical growth tip  54  is ascertained to be above the position on the spring  38  where attachment  56  and training/tuning is to begin. Bending may be carried out at a location spaced down from the tender growing tip where the stem has begun to harden but is still receptive to bending without breaking. It is when this hardened yet supple part of the stem is directly across from the selected position on the spring that the movement of bending the stem is to be carried out. As can be seen in  FIGS. 12 and 16 , the stem  60  is bent so that the arc of the bend is as open as possible. Sharp bends are preferably avoided as these could cause unnecessary damage to the plant  46 . The arc of the bend may be from the soil line  50  to the position on the spring  38  where training/‘apical tuning’ is to begin. Using a form of wire, clip, string  56  or other connector the hardened/supple portion of the plant  46  is tied down/attached  56  to the spring  38 . Again it is preferable to leave the fragile growing tip  54  alone and that it not be tied down to the spring  38 . 
         [0043]    The plant  46  is then observed as it reorients to its new position so that the apical growing tip  54  begins to grow vertical  64  again due to the effects phototropism and gravitropism. This new position overcomes the apical dominance of the apical growing tip  54  and the effect of auxin on the axillary shoots  58  is diminished while the increased exposure to light enhances axillary shoot  58  growth, and thus the axillary shoots  58  turn vertical  64  as well. Axillary shoots  58  may be thinned out  62  as shown in  FIG. 16 , or left alone as determined/decided by the grower. Subsequently as shown in  FIG. 13 , the apical growth tip  54  (what was the original apical shoot) is attached further up the arc of spring  38 . Readiness for bending is again assessed in the manner described above, and another bend is then applied to appropriate spot in the stem. The second bend, training the plant  46  up the arc and pitch of the spring  38 , continues to overcome apical dominance and exposes new axillary shoots  58  to light, thus enhancing their growth as can be seen in  FIGS. 14-15 . A sequence of additional bends are applied to the original apical shoot  54 , in the same manner up the arc of the spring  38 , continually overcoming apical dominance and exposing more axillary shoots  58  to light. Finally the original apical shoot  54  may be allowed to continue its vertical growth when the desired number of evenly proportioned branches and shoots has been obtained and apical dominance is sufficiently overcome. 
         [0044]    The above steps for training the apical tip can be applied to any desired stage in the life cycle of the plant (e.g. flowering and fruiting) and to any growing tip on the plant that may benefit from training to overcome apical dominance. Springs  38  of varying scale/dimension/pitch, while maintaining the Fibonacci/Golden Spiral pattern, can be applied to a wide range of growing situations where apical dominance is of concern. 
         [0045]    The method steps described above can be carried out rapidly with minimal labor, and require very little training to understand and perform. The system is therefore well suited to use by a large-scale commercial growing facility having multiple employees. The training of the plant can maximize utilization of artificial light and other resources supporting growth of the plants and consequently reduce costs as compared with traditional growing techniques. Furthermore, the spring-shaped support of the invention is exceptionally economical to fabricate and when compressed can be transported/stored compactly in large numbers, contributing to low cost, and can be made sufficiently durable for reuse in applications where this may be desired. 
         [0046]    It will be understood that the scope of the appended claims should not be limited by particular embodiments set forth herein, but should be construed in a manner consistent with the specification as a whole.