AU750856B2 - Horticultural container and method of use - Google Patents

Description

WO 98/23143 PCT/AU97/00789 HORTICULTURAL CONTAINER AND METHOD OF USE This invention relates to a horticultural container and method of use.

This invention has particular but not exclusive application to a horticulture pot and a re-potting method using said pot and for illustrative purposes reference will be made to such application. However, it is to be understood that this invention could be used in other applications, such as in producing horticultural containers generally.

The commercial on-growth of plants in pots is well known.

As the plants develop they go through a process called "potting on" which involves removing the plant from its pot and repotting the plant in a larger pot. Upon reaching maturity or market readiness they are placed in a pot ready for sale.

A problem with growing a plant in the confined space of a pot is that the root development is limited to the confines of the pot. This often results in the root structure "coiling" or growing in circles within the pot rather than having a downward and/or outward directionality. Thus plants become root bound and unsuitable for sale or replanting.

Accordingly, it is an object of the present invention to provide a horticultural container which substantially overcomes at least one of the foregoing disadvantages and which is efficient in use. Other objects and advantages of this invention will hereinafter become apparent.

With the foregoing and other objects in view, this invention in one aspect resides broadly in a horticultural container comprising a side wall, a base wall including a drain WO 98/23143 PCT/AU97/00789 2 hole, and a supporting base adapted to elevate said base wall above a supporting surface, said side wall being configured to form a plurality of columnar spaces spaced about said side wall and adapted to receive and guide root growth, and a tap root space of at least the depth of said columnar spaces.

The container may be any shape consistent with the function of containing the plant as a pot, planter box, seed trays, tubes or the like. For example, the container may comprise a substantially circular section pot, each columnar space being part cylindrical. The pots may be of any size maintainable by the choice of material and shape of material.

It is desired that the sizes are aligned to nursery industry standards.

Alternatively, the container may be of generally rectangular in section and preferably square. The container may have any suitable number of columnar spaces, consistent with providing the pot with adequate root growth space. For example, the preferred square pot may include four generally rectangular-section columnar spaces, each columnar space being preferably disposed at a corner of the container. In this embodiment each corner columnar space is partially separated from an adjacent columnar space by an inwardly extending vertical rib.

Preferably, the inwardly extending vertical rib is defined by the interior wall of the container and a corresponding vertical groove is defined by the exterior wall of the container, the vertical groove further facilitating portability of the container. Preferably, each corner columnar space is WO 98/23143 PCT/AU97/00789 3 overlapped by the central tap root columnar space. The central columnar space may be as deep as the corner columnar spaces or may be deeper. This ensures that the base wall drain hole is the lowest point in the container at which excess water may collect, thus preventing waterlogging of roots in the columnar spaces as they approach the bottom of the pot.

The container may be formed of a biodegradable water absorbent material. The biodegradable water absorbent material may be impregnated with additives and/or be formed of composted nutritional ingredients, elements and minerals. The additives or materials may be selected to form a balanced formula to suit the specific groups and species of plants as the pot degrades.

The biodegradable water absorbent material may be selectively impregnated with the above additives at or adjacent the corner columnar spaces but preferably the container is impregnated throughout the container material.

The biodegradable water absorbent material may comprise a comminuted mouldable pulp of organic fibrous material mixture, with a horticulturally acceptable binder. Preferably, the mixture is selected to be self binding. For example, the mixture may be selected from mixtures of commercial mulches, composted organic matter, paper, composted sawdust, coco peat, ti-tree oil process mulch, mushroom compost, bagasse and wheat stubble, the combination being selected to self bind under autoclaving.

Further, the horticultural container may be colour coded to indicate a type, grade or quantity of additive or pot material composition, or alternatively the colour coding may WO 98/23143 PCT/AU97/00789- 4 also be used to indicate a species, flower colour or other character of a plant. Colour coding has the advantage of providing visual impact at the point of sale and allows ease of identification for sorting and processing. The pots are preferably printable to enable the printing graphics, logos, labels, decals or the like to the outer surfaces.

The container may also include one or more visible apertures, wherein the observed presence of roots indicates when the plant should be re-potted.

The most common method of determining when a plant needs to be potted-on is to physically remove the plant from the container and to look at the root growth. Of course, it is not ideal to keep disturbing a potted plant. Other methods are to look at the health and growth of the plant. However, the slightest difference in the plant's health or growth may mean that the roots are already coiling or the plant is root bound.

Accordingly, it is a further object of the present invention to provide a horticultural container which substantially overcomes at least one of the foregoing root observation disadvantages and which is efficient in use.

With the foregoing and other objects in view this invention resides broadly in a horticulture container including a base wall and a side wall having one or more apertures provided therein above and in the region of the base wall, wherein the observed presence of roots at said apertures indicates when the plant should be re-potted.

The aperture may be positioned in any wall of the container. It is preferred that the aperture is positioned in WO 98/23143 PCT/AU97/00789 a wall adjacent to the base of the container and at a suitable height so as to observe the root growth prior to impingement on the base of the container, the precursor to becoming root bound. In practice, reasonable pot life is gained without root binding using apertures positioned at approximately 15% of the pot height from the base wall to the upper rim, or less.

Preferably, the lower edge of the apertures are located less than 10mm above the base wall.

There may be more than one aperture, in order to see root growth throughout the extent of the container. For example, if the container is rectangular or square, one or more apertures may be included in each wall, dependent of the size of the container. Alternatively, if the container is round, several apertures may be spaced around the container.

A difficulty with the provision of drainage holes or the like in horticultural pots is the tendency for the potting medium to be washed out of the holes. Accordingly drainage holes are sometimes provided with a screen material to retain the potting mix values.

In the present case of observation apertures, no screening material may be used. Accordingly the apertures are preferably large enough to provide a visual indication, but not so large as to allow significant wash out of potting mix. It has been determined that a slot provides the best compromise between permitting visual identification of root growth to potting-on stage, and reduction of soil wash out. Particularly, a horizontal slot is preferred, since in practice it has been determined that for a given slot size, a vertical slot allows WO 98/23143 PCT/AU97/00789 6 more wash out than a horizontal slot. Preferably, the slot has a vertical extent of less than 3mm.

At each stage of "potting on" and at the final stage of planting into the ground there is a risk that the plant will suffer root shock or root damage or disturbance upon its removal from the container and exposure to atmosphere. The plant will require a period of adjustment before its growth patterns will return to normal.

Further, after each stage of "potting on" it is necessary to retrieve the pot, carry and return the pot to a depot, clean, disinfect and dry the pot, and stack the pot for storage until further use. This can be time consuming and costly if done on a large scale as in plant nurseries.

Horticultural containers as described above have the advantage that the water permeable, biodegradable material permits penetration of roots and utilisation of the nutritive values of the material by the plant when the container is buried in soil.

Accordingly, it is a further object of the present invention to provide a re-potting method and a planting method which substantially overcomes at least one of the foregoing disadvantages and which is efficient in use.

With the foregoing and other objects in view, this invention resides broadly in a potting-on method including growing a plant in a horticultural container as described above, and re-potting the plant into a second larger container without removing the plant from the horticultural container.

In a further aspect, this invention includes a method of WO 98/23143 PCT/AU97/00789 7 planting a plant including growing a plant in a horticultural container as described above and planting the plant into the ground without removing the plant from the horticultural container.

In order that this invention may be more readily understood and put into practical effect, reference will now be made to the accompanying drawings which illustrate a preferred embodiment of the invention and wherein: FIG. 1 is a side perspective view of a horticulture pot; FIG. 2 is a bottom perspective view of the horticulture pot; FIG. 3 is a range of sizes of the horticulture pot; FIG. 4 is a side view of the horticulture pot, and FIG. 5 is a top plan view of the horticulture pot.

With reference to the accompanying drawings there is illustrated a highly preferred embodiment of a pot 10 according to the invention.

The drawings illustrate a rectangular section tapered biodegradable pot. The pot 10 has a castellated design such that a vertical groove 11 is formed in each external wall, with a corresponding vertical rib 12 being defined by the internal wall. The vertical grooves 11 in the external walls facilitate handling of the pot, by providing a protruding portion 13 which may be gripped, and the internal vertical ribs 12 serve to partially separate adjacent columnar spaces 14 and prevent root coiling.

Each columnar space 14 is disposed in a corner of the pot and is generally rectangular in section. Each of the corner WO 98/23143 PCT/AU97/00789 8 columnar spaces 14 is overlapped by a central columnar tap root space 15. The central columnar tap root space 15 extends to the base wall 16 of the pot which comprises an elevated inner surface 17 supported on footings 18 in each corner. The footings 18 raise the inner surface 17 of the pot 10 off the ground thereby facilitating drainage and minimising disease attack. The base wall 16 of the pot has drainage apertures 19.

Horizontal slots or apertures 20 are formed in the vertical grooves/ribs in the walls adjacent to the base wall 16 of the pot. When root growth appears through these slots 20 or apertures it is a visual indication that the plant should be re-potted as the roots are about to impinge on the floor of the pot and commence coiling.

The pot 10 is formed of a fibrous water absorbent material comprising a comminuted pulp of ti-tree oil process mulch, bagasse, mushroom compost and wheat stubble having a moisture content of about 10-15% to form a mouldable material. A colouring material selected from food dyes is added to distinguish the batch by composition. The pot 10 is moulded and then autoclaved at about 65 degrees Celsius, whereupon the material forms its own binder. It will be recognised by persons skilled in the art that the inherent variability of the organic materials requires some testing to produce the best result from a particular batch. It is desirable to use the known properties of the mushroom compost to adjust the NPK value of the pot.

In use, a plant is potted in the pot 10 and root growth initially occurs in the normal manner. Because moisture is WO 98/23143 PCT/AU97/00789 9 attracted to the pot and because the pot includes fertilising additives, the roots are attracted to grow outwardly and down the walls of the pot 10. Furthermore, the roots tend to grow in columns in the columnar spaces 14 defined by the pot Root coiling is inhibited by the presence of the vertical ribs which inhibit intercolumn root growth. Accordingly, the four columns of roots maintain good directionality.

When root growth occurs at the slots or apertures adjacent the bottom of the pot, it is a visual indication the plant should be re-potted before root coiling occurs at the bottom of the pot or the pot is outgrown.

The plant is then re-potted to a larger pot of the same type. Because the first pot is biodegradable, the plant is not removed from the first pot. Rather, the first pot is simply placed in the second larger pot and the first pot is allowed to decompose into the surrounding plant medium.

The four columns of root growth are encouraged to continue growing in the same manner in the new larger pot and the process can be repeated as many times as necessary. Upon reaching maturity or market readiness, the plant and largest pot are planted without removal of the plant from the pot.

Horticultural containers in accordance with the above embodiment have several particular advantages. The tapered construction permits high density stacking for storage and transportation. The nutritional value of the pot coupled with its biodegradability enhances the suitability of the pot for potting on or planting out. The colour coding may be readily used to indicate a different fertiliser value, nutrient type, WO 98/23143 PCT/AU97/00789 to indicate different plant species, or different variations within a species, such a flower colour. Colour coding has the advantage of providing visual impact at the point of sale and allows ease of identification for sorting and processing. The pots are printable to enable the printing graphics, logos, labels, decals or the like to the outer surfaces for promotions.

The absorbent nature of the pot material results in water from the pot medium being attracted to the pot and thus provide a moist enhanced growing medium adjacent the external walls of the columnar spaces which will induce downward growth of the roots. This combined with the coiling inhibiting configuration of the pot 10 results in enhanced production of potted plants.

The absorbent nature of the pot material facilitates treatment of disease by dip-drenching. At the same time, the elevation of the base wall above the supporting surface inhibits the influx of disease organisms through pooling at the drain hole.

It will be clear that the preferred embodiment of the present invention will substantially avoid the chance of damaging or shocking the plant's roots as the roots are never exposed to mechanical damage nor are they exposed to direct sunlight, heat or cold. Minimal root disturbance throughout the plants development encourages continuous growth and the natural symbiotic relationships between the plant and the beneficial bacteria and fungi are uninterrupted providing a balanced soil/medium environment.

The pot will reduce labour costs, reduce plant propagation, production and cultivation time and streamline WO 98/23143 PCT/AU97/00789 11 methodology. It also eliminates collection and cleaning of used pots.

It will of course be realised that whilst the above has been given by way of an illustrative example of this invention, all such and other modifications and variations hereto, as would be apparent to persons skilled in the art, are deemed to fall within the broad scope and ambit of this invention as is claimed in the claims appended hereto.

Claims (10)

1. 2. A horticultural container according to Claim i, wherein the side wall and base define a generally square pot, having four rectangular-section columnar spaces disposed at each corner of the container and partially separated by inwardly extending vertical ribs disposed therebetween.
2. 3. A horticultural container according to Claim 2, wherein said vertical ribs are moulded into the side wall.
3. 4. A horticultural container according to any one of Claims 1 to 3, wherein said side wall tapers out from said base to an open top, whereby a plurality of containers may be stacked. A horticultural container according to any one of claims 1 to 4, wherein said supporting base, base wall and side wall are integrally moulded from a biodegradable water absorbent material. WO 98/23143 PCT/AU97/00789 13
4. 6. A horticultural container according to Claim 5, wherein said biodegradable water absorbent material comprises mulched organic fibrous material and a horticulturally acceptable binder therefor.
5. 7. A horticultural container according to Claim 6, wherein said biodegradable water absorbent material comprises a comminuted mouldable pulp of organic fibrous material mixture selected from mixtures of commercial mulches, composted organic matter, paper, composted sawdust, coco peat, ti-tree oil process mulch, mushroom compost, bagasse, and wheat stubble, the combination being selected to self bind under autoclaving.
6. 8. A horticultural container according to horticultural container may be colour coded to indicate a type, grade or quantity of additive, or alternatively the colour coding may also be used to indicate a species or flower colour of a plant.
7. 9. A horticulture container according to any one of the preceding Claims, wherein said side wall has one or more apertures provided therein above and in the region of the base wall, wherein the observed presence of roots at said apertures indicates when the plant should be re-potted. A horticulture container according to Claim 9, wherein said aperture comprises a horizontal slot.
8. 11. A horticultural container according to Claim 10, wherein WO 98/23143 PCT/AU97/00789 14 said slot has a vertical extent of less than 3mm.
9. 12. A potting-on method including growing a plant in a horticultural container according to any one of claims 5 to 11, and re-potting the plant into a second larger container without removing the plant from the horticultural container.
10. 13. A method of planting a plant including growing a plant in a horticultural container according to any one of claims 5 to 11, and planting the plant into the ground without removing the plant from the horticultural container.