WO2005041641A1

WO2005041641A1 - Pot for the propagation of seeds or cuttings

Info

Publication number: WO2005041641A1
Application number: PCT/DK2004/000760
Authority: WO
Inventors: Lars Hansen
Original assignee: Ellegaard A/S
Priority date: 2003-11-04
Filing date: 2004-11-04
Publication date: 2005-05-12

Abstract

The present invention concerns compressed growth medium pots for seed or cutting propagation, where growth medium pots (2) contain growth medium (1), e.g. in the form of sphagnum, surrounded by a membrane (3), where growth medium pots (2) are produced by filling a surrounding membrane (3) with loose growth medium (1), where the pot (2) subsequently is cut off at a first height, where the pot (2) subsequently at at least a first compression is compressed from the first height to a reduced second height. It is the purpose of the invention to design compressed growth medium pots (2) so that loss of sphagnum from the sphagnum pots (2) is reduced. This may be achieved with a pot (2) as described in the introduction, if the sphagnum pot (2) after compression is provided with a bottom (4) which is fastened to the surrounding membrane (3). Hereby may be achieved that the sphagnum pot (2) is surrounded by a membrane at sides and bottom and is only open at the top.

Description

Pot for the Propagation of Seeds or Cuttings

The present invention concerns a method for compressed growth medium pots for seed or cutting propagation, where growth medium pots contain growth medium, e.g. in the form of sphagnum, surrounded by a membrane, where growth medium pots are produced by filling a surrounding membrane with loose growth medium, where the pot subsequently is cut off at a first height, where the pot subsequently at at least a first compression is compressed from the first height to a reduced second height.

The present invention also concerns a growth medium pot that may be designed as a wholly or partially filled volume where the volume may be provided with a top and a bottom and at least one side, where the volume contains highly compressed sphagnum, where the side or sides of the volume are surrounded by a first membrane, which membrane is permeable for water and plant roots.

The present invention also concerns use of a growth medium pot as described above.

US 3,375,607 discloses a pot of compressed plant growth medium expanding by contact with water into a porous loose material with increasing volume, which is surrounded by a casing compressing the pot for attaining reduced size under transport and storage, but which may be expanded to a volume which is large enough for germinating plants. The casing may consist of a plastic net which is pressed against the pot and forms it. Typically, pot and casing are expanded four to six times from storage to situation of use.

US 3,883,989 discloses growing plants in expanded sphagnum pots that are produced by mixing an aqueous bitumen emulsion with sphagnum in a critical ratio, drying the mixture and performing compression in several directions for shaping solid items. The compressed items have a thickness comprising only a small part of their original thickness. These items expand by contact with water into forming soft cakes that assume their shape without external support, but they allow normal plant and root growth. The expanded pot has a thickness which is approximately the original thickness before compression.

None of the above mentioned publications describe compressing growth medium pots in a way that can be used in practice. US 3,375,607 discloses compressing sphagnum contained in a net by compression in a tool with a top part and a bottom part without any support on the sides of the sphagnum pot. Only by using a very rigid net, one may prevent a lateral expansion of the sphagnum pot during compression, and with great probability a part of the pot may become jammed between top and bottom parts of the tool.

US 3,883,989 uses a bitumen emulsion for holding together sphagnum in the desired shape. On the fact that bitumen is environmentally hazardous, it will be directly disadvantageous to use bitumen as growth medium for plants unless there is an environmentally safe way of disposing the sphagnum pots.

WO 92/03914 discloses a method and a system for making growth medium pots, where growth medium is sucked into a surrounding tube formed of a fibre-containing material by means of underpressure. In this way, loosely compressed growth medium pots are produced.

US 6,455,149 Bl discloses pills that are water swelling and a method for making the pills. The pills are made of a growth medium which has been added various additives in the shape of means for pH adjustment, means facilitating water absorption, and means enabling making the pills by extrusion. At the same time, both fertilisers and insecticides are added. The pills are thus containing a number of environmentally damaging chemical compounds.

Sphagnum may fall off primarily from the bottom of existing sphagnum pots. This waste may be unfavourable because the wasted sphagnum act as contamination on the surroundings while at the same time the amount of growth medium in the pot is reduced. In connection with use where water is added to the sphagnum pots, loss of growth medium may also occur.

It is the purpose of the invention to design compressed growth medium pots so that loss of sphagnum from the sphagnum pots is reduced.

This may be achieved with a pot as described in the introduction, if the sphagnum pot after compression is provided with a bottom which is fastened to the surrounding membrane.

Hereby may be achieved that the sphagnum pot is surrounded by a membrane at sides and bottom and is only open at the top. It is thereby prevented that particles of sphagnum are loosened and fall off, as the surrounding membrane will hinder it from falling off the sphagnum pot, while at the same time acting as stabilising means on the surfaces surrounded by the membrane. Thus a sphagnum pot appears considerably more sturdy during finishing production and packing as well as during transport and furthermore under the subsequent use where sphagnum pots are placed on trays, and in connection with subsequent watering it is also ensured that sphagnum in wet condition does not leave the sphagnum pot. With a properly selected membrane, water permeability as well as penetration of plant roots may be optimal.

During the last compression, growth medium pots may be designed with at least one opening for receiving cuttings. Hereby may be achieved that a growth medium pot is prepared to receive cuttings right at the manufacturing. In connection with propagation by cuttings it is thus avoided forming openings by knife or other tools in sphagnum pots before a cutting is placed in the opening, and sphagnum, or other growth medium, is compressed around the cutting with fingers. As the openings are provided beforehand, it is made considerably faster to put cuttings in these openings, and because openings are provided in a pot consisting of a compressed growth medium, compression around plant stems is not needed as this operation is performed automatically by the swelling effected by the compressed growth medium pot when this is added water. Propagation of plants by cuttings thereby becomes considerably more efficient than previously for this process. Growth medium pots with well-defined openings for accommodating cuttings may enable an automatic production process in the future, where the sphagnum pots are automatically laid upon a table after which a machine fully automatically will place plant stems in the openings. In that way, propagation by cuttings may eventually be competitive as compared with propagation of plants by seeds.

Growth medium pots may be compressed about at least one projection for forming at least one through-going opening for later reception of a cutting. Hereby may be achieved that the projections ensure an opening in the growth medium pot through the entire production process, and as the compression is effected around a projecting tool part, the compressed growth medium will form a relatively stable wall towards the opening, and formation of dust during handling and transport would be minimal due to the sphagnum pot being provided with a bottom. The finished growth medium pot of high quality may thus reach the actual application.

The projections, and thereby the through-going openings, are having a design which may be adapted to the cuttings. Hereby may be achieved that adaptation to actual plants occurs during production by using projections with dimensions adapted to the actual application. The openings of the pots may in that way be adapted to a large number of different plants, where the cuttings to be propagated may have substantially different shapes and sizes. On the background that it would be very simple to switch a production plant so as to change from one type of projection to another, with a very modest increase in cost it will be possible to produce a great variation of growth medium pots that are adapted to widely different types of plants. If it is possible logistically to control a number of different variants, there may be achieved the advantage that there are optimal conditions in the growth medium pots for the actual plant variety to be propagated by cuttings.

The openings in the growth medium pots may be formed as longitudinal slots that may be adapted to cactus leaves. Hereby may be achieved that the openings are adapted to the actual shape of the cactus leaf desired to be reproduced. The case may be flat cactus leaves, or a central hole with a number of projections extending in different directions for adapting to the optimal design with regard to the actual cactus species.

The through-going openings in the growth medium pots may as a possible alternative be formed as cylindric openings. Hereby may be achieved adaptation which is particularly suited for round cuttings, however, the cylindric opening may to a limited extent also be used for cuttings deviating from the round shape, as adaptation will occur when the growth medium pots are added water so that swelling occurs.

The number of openings in the growth medium pots may be adapted to the actual plant to be propagated by cuttings. Hereby may be achieved that several individual cuttings may be placed in the individual growth medium pot, as in some cases it is desirable to dispose several independent plants close to each other where entangling of the roots maybe occurs, but with ornamental plants it will be of importance that several plants stand close together for forming the nicest possible ornamental plant as result. In particular by reproduction of certain cactus species it is suitable that several plants are planted directly beside each other. This may advantageously be done by propagation by cuttings as a plurality of cuttings can be disposed in the same growth medium pot.

Growth medium pots may be designed as a wholly or partially filled volume where the volume has a top and a bottom and at least one side, where the volume contains highly compressed sphagnum, where the side or sides of the volume are surrounded by a first membrane, which membrane is permeable for water and plant roots, where the bottom of the volume is surrounded by a second membrane, and where the first and the second membrane are joined at the edge of the volume between side and bottom.

Hereby is achieved a finished growth medium pot which initially is highly compressed and thereby takes up a minimal volume during transport, but where the growth medium pot is closed downwards, whereby waste and dust from sphagnum is completely avoided, and the sphagnum pot may by watering expand in upwards direction without any loss of growth medium to e.g. a water surface standing around the growth medium pot in connection with watering. Subsequent loss of growth medium along the bottom of the pot in connection with a possible handling of trays with plants is also reduced, as the bottom still prevents loss of growth medium in downwards direction. The two membranes may be joined by bonding, where glue insoluble in water may advantageously be applied.

The first membrane may advantageously surround the side or sides of the sphagnum pot, and the membrane may have a width exceeding the height of volume, where the surrounding membrane is bent around the edge of the volume in under the bottom of the volume, and where the first membrane may be joined to the second membrane surrounding the bottom of the volume. Hereby may be achieved a secure joining of the two membranes, since an overlapping area may appear with a size which provides that e.g. glue may form a secure joint between the two membranes.

The volume may contain at least one indentation for reception of seed or cutting. By using an indentation, efficient growth conditions for seeds or cuttings are ensured, as they are surrounded on all sides by growth medium, as a subsequent watering of the sphagnum pot will entail a partial compressing of sphagnum around seed or cutting.

The volume may contain at least one longitudinal indentation for reception of at least one cutting. Use of longitudinal indentations may be a great advantage if there is cuttings of e.g. cactus leaves are to be reproduced, where the cactus leaves are just placed in the longitudinal indentations, after which watering of the sphagnum pot is performed. Hence the cactus leaves are provided good conditions for forming roots and thereby initiate growth. Typically, by propagation of cactus, several leaves may be used in the same sphagnum pot, and in a typical sphagnum pot there will typically be a plurality of longitudinal indentations, and in practice the preferred number will be three.

By using the previously described growth medium pots, a controlled amount of water may advantageously be supplied, causing a partial swelling of the growth medium pots before transplanting cuttings or seeds, where the growth medium pots subsequently may be supplied with an amount of water causing further swelling of growth medium pots around the cuttings or seeds. Hereby may be achieved that the beginning swelling of the growth medium pots will increase the height of the growth medium pot so that it, even before setting the cuttings, has reached a height so that the cuttings are supported in a greater part of their height, and the cuttings are thereby prevented from tilting after being placed in the growth medium pots. Further addition of water will entail further swelling of growth medium which will reduce the openings in the growth medium pots so that the growth medium is squeezed against the cuttings, thus optimising the conditions for sprouting.

In the following, the invention is explained with reference to drawings where:

Figs, la-lc show a first embodiment of a cylindric growth medium pot according to the invention in perspective view, as growth medium and pot in separated condition in section, the growth medium pot in assembled state and the growth medium pot in compressed state, respectively;

Figs. 2a-2c show a second embodiment of the growth medium pot in perspective view, in uncompressed state, in compressed state and in section, respectively;

Figs. 3a and 3b show a third embodiment of the growth medium pot according to the invention in perspective view, in uncompressed state and in compressed state, respectively;

Figs. 4a-4c show a fourth embodiment of the growth medium pot according to the invention in perspective view, in uncompressed state, in compressed state and in section, respectively;

Fig. 5 shows a possible embodiment of a machine for making growth medium pots;

Fig. 6 shows an alternative embodiment of a machine; and

Fig. 7 shows an exploded view of the revolving unit itself. Fig. la shows a section of a volume of growth medium 1 of prior art which is used in the growth medium pot according to the invention. Growth medium 1 is disposed in the way described below, in a pot 2 made of fibre-containing material. The pot 2 consists of a cylindric wall 3 and a bottom 4. The material for the pot 2 is also known by itself, as well as the cylindric wall is a known design. The new feature is, however, that a bottom 4 is provided, fastened to the cylindric wall 3 by adhesives or by compression. In that case the tubular wall 3 may extend down around the bottom 4 which may just consist of a disc.

On Fig. lb the finished growth medium pot 5 is shown, and after compressing according to the method specified below, the pot assumes the shape indicated on Fig. lc and designated 5 a.

In a second embodiment of the growth medium pot according to the invention is seen on Fig. 2a and designated 10. The difference compared with the embodiment of Fig. lb is the existence of an indentation or hole 11 at the centre on top of the growth medium surface. Seed or cuttings may be provided in the hole 11. In the compressed state on Figs. 2b and 2c, seeds and cuttings are similarly disposed in indentation 11, and as the growth medium 1 expands under addition of water, growth medium 1 will be squeezed together around the seed or the cutting.

In the third embodiment of the growth medium pot according to the invention appearing on Figures 3 a and 3b, three indentations 11 are disposed at the top of the growth medium pot 20, 20a, so that three cuttings may be planted in this embodiment of the growth medium pot, both in compressed state 20a and in uncompressed state 20.

Other embodiments with still more indentations or holes 11 are possible within the scope of the invention. The fourth embodiment, shown on Figs. 4a-4c, has a largely rectangular basic shape in cross-section with rounded corners. This embodiment is designated by the number 30. In order to form the ground for certain kinds of sprouts and cuttings, e.g. cactus leaves, a plurality of elongated holes 31 are formed in parallel side by side in the growth medium 1. The holes 31 are through-going in this embodiment and thus reach completely down to the bottom 34 in the growth medium pot 30. This is also the case with the compressed state 30a seen on Figs. 4b and 4c.

On Fig. 5 is shown a possible embodiment of a machine for making growth medium pots. An automatic pot apparatus 101 is forming a tubular wall consisting of a fibre- containing material around an advancing stream of growth medium so that a growth medium pipe is formed. A more detailed description of what is occurring in the automatic pot apparatus 101 is found in WO 92/03914 which is also mentioned under the state of the art. The growth medium pipe is advanced through a not shown medium cylinder 104 towards a saw 105 to a revolving unit 109 where the growth medium pipe is shortened by means of the saw 105. On the Figure is also seen a pressing cylinder 107 and an ejecting cylinder 108.

An uncompressed pot 106 is thus placed in the revolving unit 109 by advancing the growth medium pipe and by the saw 105 performing a cut through the growth medium pipe. Subsequently, the revolving unit 109 is rotated one position forward in the direction of the arrow to a succeeding position, after which a pressing cylinder 107 and an ejecting cylinder 108 are performing, possibly simultaneously at different positions, compression of one of the growth medium pots 106, while the ejecting cylinder 108 is pressing a finished pressed pot 110 out of the revolving unit 109. Since the individual sub-processes may be performed with very great speed, one may, by means of the revolving unit 109, achieve a very rapid production of compressed growth medium pots 110. The capacity of the revolving unit 109 and the two cylinders

107 and 108 may attain a pace so that this part of the machine is following the pace with which the automatic pot apparatus 101 can operate. On Fig. 6 is shown an alternative embodiment, where the same reference numbers as on Fig. 2 are used, and therefore they are not mentioned. Fig. 3 only differs from Fig. 2 in that a further pressing cylinder 111 has been introduced.

By using two pressing cylinders 111, 107, repetition of the compression is achieved, but the number of compressions does not need to be delimited to two only, as more pressing cylinders 111, 107 may advantageously be used. The repeated compressing of growth medium pots means that the growth medium fibres attain more permanent deformation, i.e. the growth medium fibres are returning to their original shape to a lesser extent, and the growth medium pots may thus be compressed to a higher degree, and the finished growth medium pots become more uniform by the double compression, which is an advantage in packing and forwarding later.

Fig. 7 shows an exploded view of the revolving unit itself and the cylinders connected thereto. A medium cylinder 104, a saw 105 and an un-compressed growth medium pot

106 are shown. Simultaneously, a compressing cylinder 107, an ejecting cylinder 108, a rotating revolving unit 109 and a compressed growth medium pot 110 are shown. Likewise, a compressing cylinder 111 is shown. Also, there is shown a first stationary disc 113 and a second stationary disc 112.

The growth medium pipe 104 interacts with the second stationary disc 112 in which there is an opening for passage of the growth medium pipe which is shortened by means of a saw 105 operating between the revolving unit 109 and the stationary disc 112. The growth medium pot, now shortened, is transported in the rotating revolver unit to a first compressing position where pressing cylinder 111 performs a first compression of the growth medium pot. Subsequently, in next position for the revolving unit, pressing cylinder 107 performs a further compression of the growth medium pot, where the growth medium pot in the succeeding position of ejecting cylinder 108 is pressed out of the revolving unit and through an opening in the first stationary disc 113 so that a finished product 110 appears. The finished product 110 may then subsequently be placed in a packing by handling means, or possibly be packed in a container for further transport. Growth medium pots made as indicated on Figs. 5 - 8 are provided with bottom after the final compression. By compressing the growth medium pot, the surrounding membrane is not compressed but is still displaying the width in which the membrane was cut off after being filled with loose sphagnum. The excess width of the membrane is compressed on the top and bottom of the sphagnum pot during compression. Thereby, the membrane has contact around the edges of the sphagnum pot with an area located on the bottom. A flat membrane item with a shape adapted to the actual bottom may then be fastened to the surrounding membrane. Joining of the membranes is effected by bonding with a glue that is not soluble in water.

The flat membrane forming the bottom may in an alternative embodiment form a common bottom of a plurality of coherent sphagnum pots.

Claims

1. Method for producing growth medium pots for plant propagation, where growth medium pots contain growth medium surrounded by a membrane, where growth medium pots contains growth medium enclosed by a membrane, where the growth medium pots are produced by filling a surrounding membrane with loose growth medium, where the pot subsequently is cut off at a first height, where the pot subsequently at at least a first compression is compressed from the first height to a reduced second height, characterised in that after compression, the pot is provided with a bottom which is fastened to the surrounding membrane.

2. Method for producing growth medium pots according to claim 1, characterised in that the pot at least during the last compression is formed with at least one opening for receiving a cutting.

3. Method for making growth medium pots according to claim 1 or 2, characterised in that the growth medium pots are compressed about at least one projection for forming at least one opening.

4. Method for producing growth medium pots according to one of claims 1 - 3, characterised in that projections and thereby the associated openings have a shape which is adapted to the shape of the cuttings.

5. Method for producing growth medium pots according to one of claims 1 -4, characterised in that the openings in the growth medium pots are formed as longitudinal slots that are adapted to cactus leaves.

6. Method for producing growth medium pots according to one of claims 1 -5, characterised in that the openings in the growth medium pots are shaped as through- going cylindric openings.

7. Method for producing growth medium pots according to one of claims 1 -6, characterised in that the openings in the growth medium pots are adapted to the actual plants to be propagated by cuttings.

8. Growth medium pot designed as a wholly or partially filled volume where the volume has a top and a bottom and at least one side, where the volume contains highly compressed sphagnum, where the side or sides of the volume are surrounded by a first membrane, which membrane is permeable for water and plant roots, characterised in that the bottom of the volume is surrounded by another membrane, where the first and the second membrane are joined at the edge of the volume between side and bottom.

9. Growth medium pot according to claim 8, characterised in that the first membrane surrounding the side or sides of the sphagnum pot has a width exceeding the height of volume, that the surrounding membrane is bent around the edge of the volume in under the bottom of the volume, and that the first membrane is joined to the second membrane surrounding the bottom of the volume.

10. Growth medium pot according to claim 8 or 9, characterised in that the volume includes at least one indentation for receiving seed or cutting.

11. Growth medium pot according to one of claims 8 - 10, characterised in that the volume includes at least one longitudinal indentation for receiving at least one cutting.

12. Use of a growth medium pot as specified by the method specified in at least one of claims 1 - 7 and further specified in at least one of claims 8 - 11, characterised in that by using the growth medium pots a controlled amount of water is supplied which causes a partial swelling of the growth medium pots before transplanting cuttings or seeds, and that the growth medium pots subsequently are supplied with an amount of water causing further swelling of growth medium pots around the cuttings or seeds.