1. Field
The technical field of this invention relates to planters for raised garden beds, specifically to planters high enough to eliminate or minimize stoop labor, as may be preferred.
2. Prior Art
An important part of vegetable production is not amenable to mechanization. Stoop labor is required. Meeting this requirement is increasingly difficult, as the potential labor pool ages and its physical fitness declines. Getting older and/or less fit is also affecting the capacity of people to continue home gardening and community gardening.
Raised beds are increasingly common in commercial agriculture and in home and community gardening. In comparison to growing plants at grade, raised beds offer better water and cold air drainage, earlier soil warmth, which promotes earlier plant growth, and reduced fertilization and weed control needs. Efficient drip irrigation systems work well in raised beds.
But the height of most raised beds only slightly reduces how much people have to stoop when the crop or task is not amenable to mechanization or the use of long-handled tools. Most raised beds do not have containment structures. And without a containment structure, raised beds are subject to erosion and need to be reformed regularly. Erosion also creates a disincentive for practices that over the medium and long term improve the productivity of the soil.
The advantages of raised beds have led to the development of a variety of containment structures, called planters. However, planters are rarely used in commercial agriculture due to their cost. When constructed to a height that eliminates stoop labor, the planters of the prior art are prohibitively expensive for farmers and too costly for most gardeners.
Planters as represented in the prior art typically rely on the pre-existing rigidity of structural materials like wood, stone, concrete, or plastic facsimiles of same, to resist the lateral earth pressure that results when gravity interacts with the internal friction of the soil mass. These construction materials are bulky and costly. Except for the materials made of synthetic polymers sometimes employed, they are also very heavy, a factor adding to transport and construction costs. In its wooden embodiments, the structural integrity of the prior art is degraded by biological activity engendered by the moist soil required for growing the plants of interest to farmers and gardeners. In the prior art, the replacement of construction materials is difficult and/or costly.
Accordingly, there is a need for planters that are lightweight and affordable, durable, easy to construct and maintain, and high enough to eliminate stoop labor.
In an embodiment of the present invention, the problem of cost inherent in the prior art is overcome by constructing a perimeter wall in large part from inexpensive, flexible materials with latent rigidity and in part from inexpensive, sufficiently rigid rods with adequate compressive strength. These materials enable the efficient and effective use of crossties.
Flexible wire mesh is formed to fit a rectangular perimeter frame of pre-determined width, length and height. Rods held against the inside corners of the formed mesh are attached to other rods fixed as corner posts at a predetermined spacing outside the formed mesh. Other rods brace these corner posts. Wire is cut to length to use to tie the inner and outer rods and for other attachments. Other rods are interlaced vertically through the horizontal wires of the mesh. These rods are placed so that they push the bottom horizontal wire down, the top horizontal wire up, and increase the distance the other horizontal mesh wires travel between fixed corner posts, whereby the rigidity of the perimeter frame is increased.
A textile with adequate vertical and horizontal tensile strength lines the perimeter frame, providing a barrier impervious to soil. The textile encloses the top horizontal wire of the mesh within a hem held fast by wire. A narrow band of the textile is placed as an underlay at right angles to the perimeter wall towards the interior of the embodiment at its base.
Wire is also cut to length to use as crossties to hold opposite side walls straight and upright. Crossties enable the lateral earth pressure pushing against one side to resist the lateral earth pressure pushing against the side opposite.
The first embodiment forms a rectangle in a plan view, wherein the end walls, or ends, are the width wise walls and the side walls, or sides, are the length wise walls. An embodiment could be a square in a plan view. The present invention can also be embodied in other forms.
The height of the first embodiment is somewhat higher than a standard dining table. An embodiment can be made higher or lower. The width of the first embodiment is approximately twice the depth of a normal kitchen counter. This width permits access to the middle of the top surface with minimal strain. The present invention can be embodied in other widths.
This description of the width and height of the first embodiment might suggest that a preferred length is indicated by the relative dimensions of
The number of horizontal and vertical wires in the mesh 220 shown in
Throughout this description a horizontal wire refers to a length wise wire of a wire mesh, and a vertical wire refers to the width wise wire of a wire mesh.
In
The quantity of crossties 520 shown in
Except for wire used as crossties, wire used for attachments is not shown in
The connections between the parts of my planter are seen more clearly in
The corner posts 110 reach a height above the ground that is greater than the width, or height as it becomes, of the wire mesh. The extra height is to allow for levelling of the top of the perimeter frame in the case of uneven ground.
The length of the level braces 114 is equal to the pre-determined width wise distance between the corner posts at ground level. The level braces 114 help maintain the plumb of the corner posts 110. To maintain the pre-determined width of the embodiment, they are positioned so that their ends butt against the corner posts 110. Level braces 114 are installed at two heights. The lower brace 114 is at a height approximately equal to the midpoint of the predetermined height of the planter. This brace 114 reinforces the rigidity of the ends of the perimeter wall. The higher level brace 114 is placed at approximately the predetermined height of the embodiment and helps maintain the integrity of the upper end corners, especially against accidental blows.
The angled braces 112 are fastened to the corner posts 110 at or somewhat below the predetermined height of the planter. The angled braces are positioned outside of the corner posts and outside of the mesh 220 at the sides of the planter. The angled braces help maintain the plumb of the corner posts 110. The angled braces also help maintain the integrity of the upper end corners of the planter against accidental blows. By tying each angle brace 112 with wire from a point along the half of its length closest to the ground back to the base of the corner post, the angle brace is made more effective.
A method to attach the braces 112 and 114 to the corner posts 110 is to drill holes'through the rods at appropriate places and then thread wire through the holes to make an attachment. It can also be effective to loop wire around rods and fasten tightly.
The guys 116 are assembly tools and are removed after soil is placed in the planter. Theoretically, they are not required, but practically they speed assembly. They are needed if assembly occurs during windy conditions. A guy 116 comprises wire or other material and a short rod embedded in the earth in the manner of a tent peg. Guys are placed in line with the length and with the width of an embodiment. Guys help the braces 112 and 114 hold the corner posts perpendicular until soil is placed. Guys can be tested by forcefully pulling each post into the length and into the width of the planter and verifying plumb.
In the case of the mesh used in the first embodiment, it is in the approximate range of 0.4% of the lengthwise distance between corner posts. The operation is then repeated for the other section of wire mesh.
When making right angle bends in the mesh to form corners, care is taken to ensure that the graduated horizontal wires of the mesh will meet when the two sections of wire mesh are later joined. If the mesh used does not have graduated horizontal wires, this is not a concern.
The rod 210 can be effectively held in a corner in the following way. A rod is placed so that it is in contact with each of the bends of each of the horizontal mesh wires. A wire of suitable length is looped around a horizontal wire on both sides of the corner bend. The rod is between the bend of the horizontal wire and the short looped wire. The ends of the looped wire are then twisted tightly until this looped wire and the bent horizontal wire grip the now enclosed clamping rod 210. This process is repeated for all the horizontal wires and for all clamping rods.
As described previously, the wire mesh 220 is first formed in two sections and each section has two corners and an attached clamping rod 210 in each corner. In the first embodiment the perimeter frame is made in the following way.
The completion of the tasks described above will result in a perimeter frame that is reasonably but insufficiently rigid. The rigidity of the perimeter frame is augmented by increasing the distance travelled by the horizontal wires between corner posts and by stretching the vertical wires. This is accomplished by the use of a plurality of tensioning rods 310. The tensioning rods are trimmed to a length equal to or very slightly longer than the nominal width of the wire mesh. Each tensioning rod 310 is interlaced vertically in the wire mesh 220. Adjacent horizontal wires between the top and bottom wires are on alternate sides of each rod. The bottom end of the rod is centered over the bottom horizontal wire. The top horizontal wire is pulled up with some effort and centered on the top end of the rod. Adjacent tensioning rods are placed on opposite sides of the same horizontal wire. Normally one or several vertical mesh wires will separate adjacent tensioning rods.
Because tensioning rods 310 are also used in conjunction with crossties 520 as described below in the discussion of
Tensioning rods 310 are added until ends and sides are sufficiently rigid. Sides, especially, are made equally rigid, or close to it.
In the first embodiment textile of pre-determined length, width, and weight is extended around the interior of the perimeter frame until it overlaps itself. The width of the textile is sufficient to allow an underlay 420-1 and a hem 420-2. An underlay 420-1 approximately 75 mm wide is sufficient. A hem approximately 25 mm wide is sufficient.
The hem 420-2 provides a means to attain adequate horizontal tautness in the textile liner 420 because the top horizontal wire of the wire mesh 220, which it surrounds, is interrupted along its length by the ends of vertical mesh wires and tensioning rods 310. These keep the hem from sliding horizontally. The underlay 420-1 and the hem 420-2 together provide a means to make the textile liner 420 vertically taut as the rising level of soil holds the textile to the ground and removes slack by pushing the liner into the mesh. A method to install the textile liner is as follows.
A textile liner 420 of sufficient strength needs only one layer to make the perimeter frame of mesh and rods into a perimeter wall that will retain soil. The protection provided to the textile by UV inhibitors can be augmented by means as simple as growing leafy plants, such as creepers, on the exterior of the perimeter frame. Some gardeners may prefer to install a skirt made of dried grass or other material to serve as a sunscreen.
It is also possible to reasonably align the lifecycle of the textile with the lifecycle of the wire mesh by using more than one layer of textile. In this case, an outer layer will screen an inner layer. To install a double layer it is preferable, although not necessary, to roll out a single sheet of textile of adequate length. The installer proceeds as described above for the first layer, except that the hem attachment can be more sparing. The second layer is laid against and over the first layer and the hem is formed and ends joined as described previously.
Upper level crossties 520 are attached in a manner that allows for their occasional replacement and/or for the occasional replacement of rods. Lower level crossties will not have to be replaced. Their function is to help provide form and strength during the loading of soil. Because of the inertia of the placed soil at ground level, they become structurally redundant.
Each base level crosstie 520 is preferably passed below the underlay 420-1 and attached to the bottom horizontal wire at points opposite. Base level crossties can be installed before the textile liner 420 is installed. It is sufficient to space a base level crosstie approximately 1.2 metres from an end or from another base level crosstie in the preferred embodiments. A base level crosstie is attached by bending and looping one end of the crosstie around the bottom horizontal wire on a side of the perimeter wall and the other end of the crosstie around the bottom horizontal wire on the other side. The length of unbent wire between sides opposite is equal to the preferred width of the embodiment.
Each upper level crosstie 520 is preferably attached in a manner that takes advantage of the stiffness of the tensioning rods 310 interlaced with the horizontal wires of the mesh 220. In the absence of a tensioning rod 310, a similar rod placed on the outside of the wire mesh 220 and held in place by the end of a crosstie will help distributes pressure more effectively over a larger surface area than would occur if an upper level crosstie was attached directly to the wire mesh.
In the first embodiment, tensioning rods 310 on sides opposite are spaced approximately 600 mm apart. This spacing corresponds to an adequate spacing of upper level cross ties 520.
Each upper level crosstie 520 passes through the textile liner 420 on sides opposite next to a tensioning rod 310. From the liner, an end of each crosstie is brought past its corresponding tensioning rod 310. It is then brought across the back of the rod and bent towards the liner on the side of the rod opposite to where the crosstie emerges from the liner. It is then fixed to a mesh wire. The operation is repeated on the side opposite taking care to ensure the predetermined width of the embodiment.
To facilitate replacement as required of tensioning rods 310, or of their own replacement, care should be taken to not over twist the ends of the upper level crossties 520. To make assembly more efficient, crossties 520 are pre-cut to an adequate length and marked in a way that will speed their installation.
Advantages and Ramifications
Embodiments of the present invention are suitable for home and community gardening and for commercial agriculture in respect to crops which otherwise demand stoop labor. Their low cost, portability and ease of installation make them economically viable. The increased productivity of labour freed from stooping adds to this viability. Embodiments can be installed in locations with poor or no soil and have soil brought to them. Only a limited depth need be comprised of soil suitable for crops.
Embodiments with less height than the first embodiment may be preferable for varieties of taller plants. In situations such as schools where children are encouraged to learn about gardening, embodiments with less height and less width than the first embodiment may be preferred. Other embodiments can serve as a pre-existing barrier surrounding in some part homes or other buildings on flood plains. In this use they would be reinforced by sandbags to maintain their integrity against flood waters. They would, nonetheless, greatly reduce the amount of sandbagging required. In this flood defence role, they could also be gardened.
Number | Date | Country | Kind |
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2000022483 | Dec 2011 | CA | national |