GB2200523A

GB2200523A - Plant propagator

Info

Publication number: GB2200523A
Application number: GB08702319A
Authority: GB
Inventors: Leonard George Sinsbury
Original assignee: Individual
Current assignee: Individual
Priority date: 1987-02-03
Filing date: 1987-02-03
Publication date: 1988-08-10
Also published as: GB8702319D0

Abstract

A plant propagator is provided with an upper container (3) and a lower container (4), the upper container (3) containing a plant growth substrate and the lower container (4) being provided with a reservoir (7). A phase separation (10) is permanently provided between the upper level of the reservoir (7) and the base of the container (3) whereby all growth of a plant (17) is oocassioned by water taken up via roots (9) extending through root holes (8) in the container (3) across phase separation (10). <IMAGE>

Description

PHASE SEPARATION GROWTH PROMOTION METHOD AND APPARATUS The present invention relates to a phase separation growth promotion method and apparatus for growing plants.

Ring culture is a well-known method of growing plants wherein a plant is situated in a suitable substrate in an open bottomed pot upon a gravel bed. The gravel bed is flushed with water, and where appropràte, plant nutrients which are taken up by the substrate and plant to promote growth of the plant. Whereas this process is satisfactory on a commercial scale it is less useful for indoor plants and for this purpose propagators have been proposed associated with the reservoirs so that pot plants can be kept continually watered. Various arrangements have been proposed to transfer water from a reservoir to the soil among which the most popular is a wick arrangement.

We have now found that the wick arrangement is not only unnecessary but counter-productive to healthy development of plants. We have found that all water necessary for optimum plant growth can be taken up by the roots alone extending into a water reservoir aCf X phase separation so that the soil or other plant support substrate does not come into direct contact with the water in the reservoir.

According, therefore, to a first aspect of this invention there is provided a phase separation growth promotion method for plants which comprises, positioning a plant in a plant growth support substrate with a sufficieni. .of moisture to commence root dev elopment, positioning said substrate immediately adjacent a water supply but spaced there above, causing the roots to protrude from the substrate and into the water whereby all growth of the plant after initial root development is mediated by water taken up by the roots across a phase separation.

It will be appreciated that the phase separation is usually an air space or a combination of an air space and a discontinuous web. Although the precise mech anism for water uptake by roots in these circumstances is not fully understood, it is believed that the plant will draw water,. and suitab1epiant growth nutrientstwhere supplied, by translocation via the roots in the normal way. However, where the substrate in which the plant is secured dries ort water is also raised by capillary action about the external faces of the roots into the substrate. Accordingly, where the plant growth substrate is provided with suitable plant nutrients, these can be dissolved and made available to the plant by water transferred by capillary or similar action of the roots across a phase separation.

In a second aspect of the invention there is provided a plant propagator comprising an upper container for plant support substrate provided with a plurality of apertures in the base thereof, a lower container nestable therewith to provide a reservoir over its lower portion, means to prevent water in the reservoir reaching the ap ortures; the arrangement being such that a plant growing in the substrate can only obtain water via roots extending below the substrate and into the reservoir via a phase separation.

The reservoir level may be controlled by a float associated with a stem riding in a float tube standing vertically within the upper container, said stem extending above the float tube to indicate the level of water in the reservoir. Alternatively, a liquid level flow control valve such as a ball valve may be positioned in or immediately above the reservoir.

The propagator may also be provided with a plurality, for example four, generally vertically a posed support canes located at their lower ends in a support collar disposed about the rim of the upper container. These canes may be located at their upper ends in a torsion plate adapted to cause the ends of the canes to flex slightly inwardly to enhance structural integrity.

One embodiment of the present invention will now be described, by way of illustration only, with reference to the Figure which shows in vertical cross section through a propagator in accordance with the present invention. A propagator (1) in accordance with this invention is formed of an upper container (3) nested with a lower container (4). The containers (3) and (4) may have any suitable transverse cross-sections such as square, rectangular, triangular or circular. Rectangular is to be preferred.

The upper container i3) terminates at its uppermost edge in a rim (2) extending about the edge thereof and terminating at its uppermost edge in an outwardly inturned rib.

The lower container (4) similarly is provided with an outwardly inturned rib for inter-engagement with the outer face of the upper container at about the point at which the rim (2) terminates in the downward direction.

The upper container (3) has positioned about its upper open end a support collar (15) provided adjacent to each corner thereof with a bore for the accommodation of lower end of a cane (16). The lower end of the cane (16) locates upon the frusto- conical portion of the corner of the upper container (3) thereby tending to direct the upper ends of the canes (16) in an outward direction. A torsion plate (not shown) provided with, in this case, four equally spaced apertures is located at the uppermost ends of the canes to stress the bottom ends of the canes against the sides of the container (3) thereby to provide structural integrity.

The collar (15) extends radially inwardly of the rim (2) so as to leave a large central aperture through which a plant (17) can conveniently and easily grow. The collar (15) also supports a float stem conduit (13) the lower end of which is formed integrally with the base of the upper container so as to form a float chamber (6) therein. The conduit (13) accommodates a float stem (12) which extends from a float (11) positioned in or below tlle float chamber (6) to its uppermost end wherein the float stem is provided with afloat stem indicator (14).

The base of the upper container (3) is also provided with a plurality of root holes (8) through which roots (9) pass in use across a phase separator (10) and into a reservoir (7). The reservoir (7) is formed at the bottom portion of the lower container (4).

In use, a plant support substrate (5) such as, for example, Levingtons compost (Levingtons is a registered trade mark) is positioned as shown in the upper container (3), a seedling or plant (17) is positioned therein C'u5t fashion and a sufficiency of water is introduced into the soil to commence root growth. No further water additions are made to the soil at all.

Water is then introduced down the float stem (13) until the indicator (14) indicates that the reservoir (7) has reached its highest level permissible so that the phase separation (10) is maintained.

The respiration of the plant will of course deplete the reservoir (7) and cause the indicator (14) to fall. Periodically, therefore, more water must be introduced down the float stem (13) to keep the reservoir from becoming completely dry.

After a short while roots from the plant (17) will penetrate the root holes (8) across the phase separation (10) and enter the water in the reservoir (7). These roots will develop to an extent necessary for the optimum growth of the plant. We have also found the soil substrate is kept damp; presumably by means of capillary ac.tion of the roots so that nutrients in the soil substrate (5) can be transferred to the plant without watering from above. The plant roots that leave the top container are seen to be brown and woody over the area of the phase separation, but immediately turn to white and filamentary roots at the point of contact with the water.

Extensive trials of this system have shown excellent growth of plants treated in this way and where used with tomato seedlings heavy crops have ensued. It is believed that this is a function of the ability of the plant to form roots and take up water and nutrients under optimum conditions; since over and under-watering are automatically controlled by each plant dependent upon its particular requirements.

Comparative trials have been instigated to compare the system of the present invention against the conventional top watering plants in a plant pot. We have found that the system of the present invention provides on average superior growth characteristics to the top watering system because, it is believed, the system of the present invention is strictly plant mediated, whereas top watering of a plant tends to by cyclical and mediated by the random considerations of the operative watering the plant.

In a further embodiment of the invention the lower container (4) was replaced by a channel member formed of a commercially available guttering. The water level within the guttering was adjusted to a constant level by a ball valve, so as to be immediately below a plurality of upper containers (2) supported by the upper edges of the guttering.

This arrangement functioned in precisely the same way as the first embodiment with the exception that the upper containers (2) with associated plants could be readily removed from the guttering for the picking of fruit etc.

Accordingly, the present invention relates to a phase separation growth promotion method, to a pot plant propagator embodying the same and to a hydrophonictype system employing phase-separation techniques.

Claims

1 A plant propagator comprising, an upper container for plant support substrate, provided with a plurality of apertures in the base thereof, lower container nestable therewith to provide a reservoir over its lower portion, means to prevent water in the reservoir reaching the apertures, the arrangement being such that a plant growing in the substrate can only obtain water via roots extending below the substrate and into the reservoir via a phase separation.

2 A propagator according to claim 1 wherein the reservoir level is controlled by a float associated with a stem riding in a float tube, which then indicates the level of water in the reservoir; or is controlled by a liquid level flow control valve.

3 'A propagator according to either preceding claim wherein the substrate is a growth promoting compost.

4 - A propagator according to any preceding claim further com prising a plurality of generally vertically disposed support canes located toward their lower ends in a support collar disposed about the rim of the upper container, and located at their upper ends in a torsion plate adapted to cause the ends of the canes to flex slightly inwardly to enhance structural integrity.

5. A propagator according to any preceding Claim wherein the lower container is in the form of an elongate channel adapted to support a plurality of upper containers in spaced relation therealong.

6. A plant propagator substantially as hereinbefore set forth with reference to, and/or as illustrated in, the accompanying drawing.

7. A phase separation growth promotion method for planets which comprises, positioning a plant in a gtowth support substrate with a sufficiency of moisture to commence root development, positioning said substrate immediately adjacent a water supply but spaced thereabove, causing the roots to protrude from the substrate and into the water whereby all growth of the plant after initial root development is mediated by water taken up by the roots across a phase separation.