GB2328854A

GB2328854A - Propagator with upper and lower air vents

Info

Publication number: GB2328854A
Application number: GB9718580A
Authority: GB
Inventors: Glyn David King
Original assignee: PLYSU PLC
Current assignee: PLYSU PLC
Priority date: 1997-09-03
Filing date: 1997-09-03
Publication date: 1999-03-10
Also published as: GB9718580D0

Abstract

A horticultural propagator comprises a base/tray member 5 for a growing medium and a lid/cover member 10 having first ventilation means, the propagator having a second ventilation means at a lower position than the first. The second ventilation means may be a gap 17 between the base 5 and the cover 10 provided by ribs 16, or may be openings in the sides of the cover. The first ventilation means may be a circular ventilator 14 which may be rotated shut. The propagator may be heated and be thermostatically controlled, and hot air may exhaust from vent 14 and cooler air drawn through gap 17.

Description

PROPAGATORS This invention relates to horticultural propagators.

Conventional horticultural propagators incorporate a base or tray adapted to accommodate compost or other growing medium and a transparent lid or cover adapted to be supported on the base and to form with the base an enclosed space in which a controlled environment conducive to the germination of seeds or the growth of seedlings or plants can be maintained.

Some forms of propagator are electrically heated by heating elements located in the floor of the base or tray. The lid or cover generally incorporates an air vent in the upper surface thereof.

Conventional propagators suffer from a number of disadvantages including generation of excessive condensation which can obscure plant material from view and in extreme cases increase the moisture content of the growing medium to a level which causes damping off or other conditions deleterious to plant growth. It is an object of the present invention to obviate or mitigate these disadvantages.

The invention provides a horticultural propagator comprising a base or tray adapted to accommodate a growing medium and a lid or cover adapted to be detachably supported on the base or tray to form therewith an enclosure in which a controlled environment, can be maintained, first ventilation means being provided at an upper level of the lid or cover and second ventilation means being provided at a lower level.

By virtue of the provision of upper and lower ventilation means a controlled flow of air through the propagator may be induced.

Preferably said second ventilation means comprises a gap formed between adjacent edges of said cover and said base. The gap may be defined by projections formed on said cover or on said base serving to maintain said cover and said base a predetermined distance apart when the cover is fitted to the propagator.

In an alternative arrangement the lid or cover may comprise an upper surface and depending side and end walls engageable with complimentary upstanding walls of the base or tray, said second ventilation means comprising at least one vent opening formed in a side or end wall of said lid or cover. If desired a plurality of ventilation openings may be provided in one or more side or end walls of the lid or cover.

Preferably at least said first ventilating means comprises one or more apertures provided with control means operable to open and close same to a desired extent when required. Said control means may comprise a shutter member adapted to be moved between an open position in which said apertures permit flow of air therethrough and a dosed position in which said aperatures are dosed to prevent air flow.

Preferably said lid or cover is formed from transparent material.

Preferably also heating means is incorporated in said base or tray to impart heat to growing medium contained within the propagator during use.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying diagrammatic drawings, in which:- Fig. 1 is a perspective view of an assembled propagator constructed according to the invention; Fig. 2 is an underneath plan view of the lid or cover of the propagator shown in Fig. 1; and Fig. 3 is an enlarged fragmentary view showing a detail.

Referring to the drawings, the propagator comprises a base or tray 5 formed from opaque plastics material by injection moulding or other plastic moulding technique. The base 5 is of generally rectangular form in plan having a floor 6 and opposed upwardly and outwardly inclined side and end walls 7 and 8. An electrical heater (not shown) is incorporated in a compartment beneath the floor 6 and is supplied with electrical current through a connecting cable 9.

A lid or cover 10 formed from transparent plastics material by injection moulding or other plastics moulding technique is located above and supported on the base or tray 5. The cover 10 is of generally similar form to the base 5 but is inverted relative thereto so as to define an upper surface 11 and opposed outwardly and downwardly inclined side and end walls 12 and 13. The lower edges of the walls 12 and 13 are essentially co-extensive with the upper edges of the walls 7 and 8 of the base 5 and are provided with outwardly directed flanges 13A extending over the upper edges of the base. A circular ventilator 14 is provided centrally of the upper surface 11 of the lid and may be moved between open and closed positions by rotation of an operating knob 15. The ventilator 14 comprises first ventilation means for the propagator.

The propagator is provided with second ventilation means formed by maintaining a gap between the adjacent edges of the base 5 and lid 10 around the periphery of the propagator. For this purpose two pairs of depending projections or pips 16 of generally hemispherical form are provided on the flanges 13A of the end walls 13 of the cover 10 and are adapted to engage the upper edges of the end walls 8 of the base 5. The arrangement is such that when the lid is placed on the base a gap 17 is formed between them extending around the periphery of the propagator. This gap defines second ventilation means cooperating with the ventilator 14 to enable controlled ventilation of the propagator when required. The width of the gap may vary dependent on the size of the propagator, but will generally be under 10mm and preferably of the order of 2mm.

In use of the propagator, compost or other growing medium is placed in the base 5 and seeds, seedlings or other plant material are planted in the compost to germinate or grow on. In order to protect the seeds or plants, the cover 10 is placed over the base 5 to enclose the seeds or plants in the area defined between the lid and base, the atmosphere in which may then be controlled by means of the heater located in the base and by means of the first and second ventilating means.

The temperature of the environment within the propagator is raised to the desired level by operation of the heater which can be thermostatically controlled so as to maintain the temperature substantially constant. Adequate ventilation is however required to encourage plant growth. For this purpose the ventilator 14 may be opened under appropriate conditions, thereby permitting hotrair to exhaust from the propagator through the vent and be replaced by cooler air drawn in through the gap 17. When ventilation is no longer required closure of the vent 14 prevents air flow since rising heated air cannot escape and further air is not therefore drawn in through the gap 17. Thus by virtue of the provision of the second ventilating means defined by the gap 17, control of conditions within the propagator may be readily effected simply by operation of the vent 14.

In the absence of the second ventilating means, opening of the vent 14 produces little or no change in the environment since there is no means for hot air exhausting through the vent to be replaced and little or no air movement therefore occurs. This can result in inadequate ventilation leading to excessive condensation within the propagator. Excessive condensation obscures the lid 10 so that the condition of the plants within the propagator cannot be visually inspected without removing the lid. In some cases formation of excessive condensation results in increase in moisture content of the growing medium to an extent which results in damping off or other damage to the seedlings or plants in the propagator.

Various modifications may be made without departing from the invention. For example the second ventilation means may be provided by ventilating openings formed in the depending side walls of the lid or cover instead of or in addition to spacing the lid and cover apart. The propagator may also take a variety of shapes and sizes and alternative shapes, sizes and positions of top ventilator may be utilised. The propagator need not necessarily be heated although the provision of heating means is preferred in providing maximum control of the environment within the propagator. Where the lid and base of the propagator are spaced apart to define the second ventilating means, spacing may be effected by means other than the projections or pips described.

For example the lid may be directly supported on the base at a plurality of locations but may have intermediate portions of the edge cut away in order to define one or more slot-like apertures through which air may flow into the propagator. Where projections or pips serve to produce the gap, they may be of various shapes, sizes and numbers and may be formed on or attached to the cover or the base or both.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

Claims:

1. A horticultural propagator comprising a base member or tray adapted to accommodate a growing medium and a lid or cover member adapted to be detachably supported on the base member or tray to form therewith an enclosure in which a controlled environment can be maintained, first ventilation means being provided at an upper level of the lid or cover member and second ventilation means being provided at a lower level.

2. A horticultural propagator according to claim 1 wherein said second ventilation means comprises a gap formed between adjacent edges of said cover member and said base member.

3. A horticultural propagator according to claim 2 wherein said gap is defined by projections formed on one of said members serving to maintain said members a predetermined distance apart when the cover member is fitted to the propagator.

4. A horticultural propagator according to claim 3 wherein the width of said gap is lOmm or less.

5. A horticultural propagator according to claim 4 wherein the width of said gap is of the order of 2mm.

6. A horticultural propagator according to claim 1 wherein said lid or cover member comprises an upper surface and depending side and end walls engageable with complimentary upstanding walls of the base member or tray, said second ventilation means comprising at least one vent opening formed in a side or end wall of said lid or cover member.

7. A horticultural propagator according to claim 6 wherein a plurality of ventilation openings are provided in one or more side or end walls of said lid or cover member.

8. A horticultural propagator according to any preceding claim wherein at least said first ventilating means comprises one or more apertures provided with control means operable to open and close same to a desired extent when required.

9. A horticultural propagator according to claim 8 wherein said control means comprises a shutter member adapted to be moved between an open position in which said apertures permit flow of air therethrough and a dosed position in which said apertures are dosed to prevent air flow.

10. A horticultural propagator according to any preceding daim wherein said lid or cover member is formed from transparent material.

11. A horticultural propagator according to any preceding claim wherein heating means is incorporated in said base member or tray to impart heat to growing medium contained within the propagator during use.

12. A horticultural propagator substantially as hereinbefore described with reference to the accompanying drawings.

13. Any novel subject matter or combination including novel subject matter disclosed herein, whether or not within the scope of or relating to the same invention as any of the preceding claims.