WO2000004756A1

WO2000004756A1 - Planting medium and method for using the same

Info

Publication number: WO2000004756A1
Application number: PCT/GB1999/002399
Authority: WO
Inventors: Dermot Christopher John Barrow
Original assignee: Dermot Christopher John Barrow
Priority date: 1998-07-23
Filing date: 1999-07-23
Publication date: 2000-02-03
Also published as: AU5056699A; GB9816110D0

Abstract

A planting medium is disclosed which comprises from 40-90 % by weight of a first component and from 10-60 % by weight of a second component, the first component comprising particles of cork and the second component comprising expanded vermiculite. A preferred medium contains, by weight, about 40 % cork particles; about 25 % dried solid matter derived from seaweed or other marine or littoral plant source; about 20 % expanded vermiculite; and about 15 % expanded pearlite. Nutrients may be included in the medium. The planting medium may be used in particulate form or in compacted form, e.g. as seed blocks. In a preferred embodiment, the planting medium is encapsulated together with a pre-germinated seed in a water-permeable envelope, e.g. one formed of tea bag paper.

Description

PLANTING MEDIUM AND METHOD FOR USING THE SAME

This invention relates to a planting medium and to a planting method which utilises this medium.

An object of this invention is to provide a versatile planting medium which in certain embodiments can be machine-manufactured and can be used in a variety of different conditions and with different types of seed.

According to one aspect of the present invention, there is provided a planting medium which comprises a water-permeable envelope material containing a pre- germinated seed, optionally together with one or more of: (a) a growth promoter, (b) a pest control agent, (c) a swelling agent, and (d) a water retention agent .

In a modification of this aspect of the invention, the seed is not pre-germinated. This embodiment is not currently preferred.

According to another aspect of the invention, there is provided a method of planting seeds, which comprises: packaging the seeds one by one into individual water-permeable envelopes, optionally together with one or more of: growth promoters, pest control agents, swelling agents; and placing the envelopes into or onto the growing medium.

According to a currently preferred aspect of the invention, there is provided a planting medium which comprises from 40-90% by weight of a first component and from 10-60% by weight of a second component, characterised in that said first component comprises particles of cork and said second component comprises expanded vermiculite.

The presence of expanded vermiculite confers upon the planting medium the capability of absorbing water. Vermiculite is a chemically inert hydrous magnesium silicate with varying amounts of aluminium and iron present. Typically it has a specific gravity of 2.3 and a hardness of about 1.5. When heated, vermiculite expands, increasing its volume by a factor of around 6- 20. The bulk density of the expanded vermiculite is generally in the range from 80-160 kg/m . Its cellular structure assists in retaining water and also encourages capillarity.

The mixture of cork particles and expanded vermiculite provides a planting medium in which seeds may germinate and grow readily. As will be explained hereinafter, the planting medium may be encapsulated together with a seed in a water-permeable envelope which permits easy transportation and planting to be carried out.

The first component is advantageously a mixture comprising (a) particles of cork and (b) dried solid matter derived from seaweed or other marine or littoral plant source. The cork particles can be the residual material (normally regarded as waste) which remains after bottle corks have been stamped or pressed out from blocks of cork. The seaweed or other marine or littoral plant source material can be the dried solid residue remaining after alginate extraction. The dried solid matter may be derived from seaweed comprising Ascophyllum nodosum and/or Laminaria Fucus chondrus. Other sources for this component include fibrous plant material such as dried samphire ( Crithmum maritimum) . Preferably the planting medium comprises from 50- 75% by weight of said first component and from 25-50% by weight of said second component, and more preferably from 60-70% by weight of said first component and from 30-40% by weight of said second component.

The first component of the planting medium preferably comprises from 2-5 parts by weight cork particles and from 1-3 parts by weight dried solid matter derived from seaweed or other marine or littoral plant source; the most preferred composition is from 3- 5 parts by weight cork particles and from 2-3 parts by weight dried solid matter derived from seaweed or other marine or littoral plant source.

The second component of the planting medium is advantageously a mixture comprising (a) expanded vermiculite and (b) expanded pearlite. This second component advantageously comprises from 2-6 parts by weight expanded vermiculite and from 1-8 parts by weight expanded pearlite; the preferred mixture is from 3-5 parts by weight expanded vermiculite and from 2-6 parts by weight expanded pearlite.

Expanded pearlite is beneficial in the planting medium of this invention because it adds density to the overall mixture. Pearlite is a volcanic glass of rhyolitic composition which expands rapidly or "pops" when heated. The expanded material resembles an artificial pumice, having a cellular structure made up of many interconnecting channels and microcavities .

One embodiment of the planting medium comprises, by weight, from 30-50% cork particles; from 10-35% dried solid matter derived from seaweed or other marine or littoral plant source; from 10-30% expanded vermiculite; and from 10-30% expanded pearlite. The currently preferred combination of ingredients is, by weight, about 40% cork particles; about 25% dried solid matter derived from seaweed or other marine or littoral plant source; about 20% expanded vermiculite; and about 15% expanded pearlite.

The particles of cork are advantageously derived from a hardwood species, preferably oak. The particles of cork advantageously have a size distribution such that 80% by weight, and more preferably 95% by weight, of the particles are in the range from l-4mm.

The expanded vermiculite advantageously consists of particles having a size distribution such that at least 80% by weight, and more preferably 95% by weight, of the particles are in the range from l-5mm. It is preferred that at least 70% by weight of the expanded vermiculite particles are in the range from 2-3mm.

A planting medium in accordance with this invention preferably includes plant nutrient additives. These can include soluble sources of the elements N, P and K. It is preferred that nitrogen is present at least in part as urea. Other forms of nitrogen may also be included, for example as nitrates and/or as ammonium compounds. Phosphorus may be present as the pentoxide or a derivative thereof; the source of potassium may be a salt, e.g. potassium sulphate. Ammonium citrate may conveniently be included as one of the additives. Trace elements, e.g. B, Mg, Fe and Mn, may also be included.

A planting medium in accordance with the invention may be used in particulate form. Alternatively, the medium may be used in compacted form - e.g. as a seed block or as an assembly of seed blocks.

In one group of embodiments, the planting medium is in packaged form. In these embodiments, the planting medium preferably includes a seed. Suitable packaging material includes water-permeable envelopes, preferably formed of a cellulosic material. A highly porous paper having a weight in the range 25-60 gram per square metre (gsm), preferably around 40 gsm, is suitable. The currently preferred material is the porous paper used in the manufacture of tea bags - this will be referred to herein as "tea bag paper".

The water-permeable envelopes described above can be manufactured and filled with planting medium and seed by adapting the machinery conventionally used to manufacture tea bags.

A plurality of such envelopes may be joined together to form a sheet or web. The or each envelope preferably includes a seed, which may be a pre- germinated seed. The pre-treatment used to give the required degree of germination preferably involves passing steam over platens of seeds in a controlled environment, e.g. in a germination cabinet, until the seed case cracks and the first signs of the radix become visible. At that time, the seeds are removed from the cabinet and further germination is arrested by coating them with a powdered mineral, e.g. gypsum or a clay. This powder may include one or more additives to assist the growth of the plant, e.g. growth promoters and/or pest control agents . These additives can be selected in accordance with ( 1 ) the type of seed being incorporated into the envelopes and ( 2 ) the location and conditions in which the seed is to be grown. The addition of such "agrochemicals" provides a highly effective mode of use, since they are directly in contact with the seed. This minimises the quantities required for effective action. The coating of the pre- germinated seed may be achieved by gently rolling the seed in the mineral powder.

The invention also provides a method of growing a plant, which comprises packaging a seed together with a planting medium as defined herein in a water-permeable envelope; and placing the packaged seed at the location where the plant is to grow.

Another aspect of the invention provides a method of planting seeds, which comprises: packaging seeds one by one into individual water-permeable envelopes together with a planting medium as defined herein; and placing the packaged seed at the location where the plant is to grow.

An array of water-permeable envelopes each containing a seed and a planting medium in accordance with this invention may be laid out in a field mechanically, e.g. using a tractor. The array of envelopes may be rolled onto a rod or bar for dispensing purposes. An array of this type may also be used to plant rice in a paddy; in this application, the content of pearlite in the planting medium is preferably increased to aid in retaining the envelope array on the sub-aqueous surface.

Preferably, the envelope is formed of a cellulosic material, e.g. paper. The currently preferred material is a highly porous paper of a weight in the range 25-60 gram per square meter (gsm), preferably 40 gsm, for example porous paper such as that conventionally used in the manufacture of tea bags. The envelopes may be produced singly or as a strip or a web. When in this form, the envelopes may be generated from two webs of paper (which will constitute the upper and lower sheets of the envelope) which are passed . through a forming machine which is programmed to form a plurality of envelopes at predetermined spacings along the web. Each of the envelopes has inserted therein a pre-germinated seed, preferably together with a preselected growth medium and one or more pest control agents as described above.

The dimensions of the envelope(s) will be selected according to the seed being grown and the spacing required between plants. For ease of manufacture, the spacing requirement may be achieved by filling only preselected ones of the envelopes with seed; other envelopes (which may be the majority) will then be empty or "blind". An individual envelope may be, for example, from 3-10 cm in length and from 2-10 cm in width.

The capillarity of the envelope medium makes it possible to use one or both ends of a relatively long web as a means for collecting water (e.g. from a trough or ditch or from a piped supply) which is then conveyed along the length of the web and hence into the individual seed-containing envelopes, thereby encouraging growth of the seeds.

One or more of the following objectives and/or benefits may be achieved in preferred embodiments of the invention:

1. The system may minimise the number of times physically fragile plants need to be lifted and transplanted during their growing cycle. In fact, the need to lift or transplant seedlings may be eradicated in some cases.

2. The amount of agro-chemicals used during the growth cycle may be reduced compared to conventional techniques and may reach "ultra-low levels" - ULLLs.

3. By using the medium of this invention, unskilled field labour and the environment - especially in the developing world - are protected from exposure to harmful or dangerous chemicals.

4. Further, the amount of water used during irrigation may be minimised; and the water may be supplied specifically to the required growing plant only without feeding weeds or other non-crop plants.

5. Adoption of the present invention is expected to reduce the amount of labour, chemicals, plant- handling, watering and spacing required for successful crop-growing without detriment to the quality of plant and vegetable products. In turn, this may reduce costs and thereby increase profits.

In presently preferred embodiments of the invention, the following components and techniques are adopted:

1. Individual pre-germinated seeds - biomass - and a pre-determined mix of agro-chemicals may be incorporated into an envelope using infuser paper with high capillarity capability. 2. Pre-germinated seeds of either food plants or flowers are first individually encapsulated in an inert clay or gypsum; if desired they may be further coated with or dipped in a bird-repellant material. The encapsulating process increases the seed volume, thereby facilitating handling, and also inhibits the germinated seed from continuing its natural life-cycle ( suspended animation for approximately 12 months may be achieve ) .

3. The seeds are individually loaded - one-at-a- time - into either an individual envelope or into continuous bands of envelopes . The envelopes are made of highly porous and preferably 40 gsm high wet- strength paper - the paper currently used in the tea industry for tea-bags is ideal for this purpose.

4. Whilst packing the seed, a uniquely formulated biomass growing-media per plant is added to the envelope(s) with the requisite agrochemicals - feed, pesticide, fungicide, predator repellant - this in specific low-volume levels - enough to protect each seed individually with no loss by overdosing.

5. Depending on use and seed, the expanded vermiculite or similar added to the biomass ensures the large scale absorption of water when the system is used for growing in an aqueous environment - rice paddies for example - when the weight of the seed and biomass would otherwise not keep the seed submerged.

6. The mechanical delivery of the seeds is achieved in a number of ways depending on use:

* for Pot growing, the envelope may be individually loaded onto a plant pot 2/3rds filled with growing medium. After the envelope is layered into the pot, the pot is mechanically topped-up with l/3rd growing medium and either left dry until it is delivered to a greenhouse or growing shed, or is watered by overhead spray in-situ and placed for growing.

* for Tray growing, a layer of envelopes may be placed onto a tray 2/3rds filled with growth medium, the envelopes then being covered with l/3rd of the total quantity of growing medium as above .

* for Greenhouse direct growing in the earth, (e.g. tomatoes and salad crops, etc. ) the soil is prepared as per usual followed by laying envelope sheets or webs or strips onto the earth, followed by a suitable covering (typically 10/20 centimetre covering) of earth. Initial watering may be from a plastic or similar trough or dribble feed water pipe located at one end of the bed; a tail piece of the envelope paper web is simply laid into the water area. Capillary action moves water through the envelope system at a steady and regular rate without the risk of flooding or over dosing and thereby causing cold growing conditions and diluting the associated agrochemicals.

* Outside Field or Bed growing may be achieved by forming the envelopes into a continuous concertina whose dimensions are pre-set to the required growing room of the plant. The concertina may be mechanically unloaded as a continuous process from the back of a lightweight tractor via a tensing bar and a skit-ing plough.

* For example, where the fields or beds are normally furrow raised, the squares of envelopes, in a concertina, are fed onto the top of each furrow or lane. The skit-ing plough then throws a stream of earth over the envelopes - enough to keep it anchored and sub-surface. The tail of the concertina is placed into either a plastic irrigation channel or onto a dribble feed water pipe and the initial watering occurs.

Field tests have shown the paper to be physically stable in excess of 35 days - the seeds breaking through in the normal growing manner but the paper continuing to successfully perform its capillary function, and acting as a grow-medium biosphere and agrochemical container.

The invention will be illustrated further by the following Examples:

Example 1

A planting medium was formulated using the following ingredients :

Cork particles (oak): 4 kg granulated residue from a cork making plant; 95% by weight of the particles sized between 1 and 4 mm.

Vermiculite: 2 kg expanded vermiculite particles; bulk density 120 kg/rrt³; 100% of particles smaller than 5 mm; 80% by weight larger than 2 mm; 95% by weight sized at 2-3 mm.

Seaweed residue: 2.5 kg of dried, fibrous residue left after alginate extraction from seaweed collected at Tralee, Ireland; seaweed species comprising Ascophyllum nodosum and Laminaria Fucus chondrus;

Pearlite: 1.5 kg expanded pearlite; 100% of particles smaller than 5 mm; 80% by weight larger than 2 mm; 95% by weight sized at 2-3 mm.

Nutrients ; 10 g of a preformulated N-P-K (15:10:10) mix containing trace amounts of Fe and Mg.

The ingredients were intimately mixed to provide the planting medium. The medium was then placed in 2-inch pots and tomato seeds were sown in the medium ( one to each pot ) . The medium was watered and the seed germinated and grew well .

Example 2

The planting medium formulation of Example 1 was encapsulated in an envelope together with a pre- germinated seed (runner bean). The seed had been allowed to germinate up to the stage where the seed case was cracked and the radix just appearing. Then the seed was rolled in fine gypsum powder containing a commercial fungicide. The envelope was made of highly porous tea bag paper of weight 40 gsm and its dimensions were 10 cm by 8 cm. The envelope containing the seed was planted at a depth of 5 inches (12.5 cm) in a pre-prepared trench out of doors. After watering, the plant was visible above the surface of the ground after three days.

Example 3

The procedure of Example 2 was repeated using a strip of connected envelopes, every fourth one of the envelopes containing a pregerminated seed plus planting medium; intervening envelopes were empty. There was a total of thirty seven envelopes which contained ten seeds. Continued germination was complete in all ten cases, as evidenced by the growth of the plants.

Claims

CLAIMS :

1. A planting medium which comprises from 40-90% by weight of a first component and from 10-60% by weight of a second component, characterised in that said first component comprises particles of cork and said second component comprises expanded vermiculite.

2. A planting medium as claimed in claim 1, characterised in that it comprises from 50-75% by weight of said first component and from 25-50% by weight of said second component.

3. A planting medium as claimed in claim 2, characterised in that it comprises from 60-70% by weight of said first component and from 30-40% by weight of said second component.

4. A planting medium as claimed in claim 1 , 2 or 3, characterised in that said first component is a mixture comprising (a) particles of cork and (b) dried solid matter derived from seaweed or other marine or littoral plant source.

5. A planting medium as claimed in claim 4, characterised in that said first component is a mixture comprising (a) particles of cork and (b) dried solid matter derived from seaweed comprising Ascophyllum nodosum and/or Laminaria Fucus chondrus.

6. A planting medium as claimed in claim 4 or 5, characterised in that the dried solid matter derived from seaweed comprises the residue after alginate extraction.

7. A planting medium as claimed in claim 4, 5 or 6, characterised in that said first component comprises from 2-5 parts by weight cork particles and from 1-3 parts by weight dried solid matter derived from seaweed or other marine or littoral plant source.

8. A planting medium as claimed in claim 7, characterised in that said first component comprises from 3-5 parts by weight cork particles and from 2-3 parts by weight dried solid matter derived from seaweed or other marine or littoral plant source.

9. A planting medium as claimed in any preceding claim, characterised in that said second component is a mixture comprising (a) expanded vermiculite and (b) expanded pearlite.

10. A planting medium as claimed in claim 9, characterised in that said second component comprises from 2-6 parts by weight expanded vermiculite and from 1-8 parts by weight expanded pearlite.

11. A planting medium as claimed in claim 10, characterised in that said second component comprises from 3-5 parts by weight expanded vermiculite and from 2-6 parts by weight expanded pearlite.

12. A planting medium as claimed in any preceding claim, characterised in that the medium comprises, by weight, from 30-50% cork particles; from 10-35% dried solid matter derived from seaweed or other marine or littoral plant source; from 10-30% expanded vermiculite; and from 10-30% expanded pearlite.

13. a planting medium as claimed in claim 12, characterised in that the medium comprises, by weight, about 40% cork particles; about 25% dried solid matter derived from seaweed or other marine or littoral plant source; about 20% expanded vermiculite; and about 15% expanded pearlite.

14. A planting medium as claimed in any preceding claim, characterised in that said particles of cork are derived from a hardwood species.

15. A planting medium as claimed in claim 14, characterised in said particles of cork are derived from oak.

16. A planting medium as claimed in any preceding claim, characterised in that said particles of cork have a size distribution such that 80% by weight of the particles are in the range from l-4mm.

17. A planting medium as claimed in claim 16, characterised in that said particles of cork have a size distribution such that 95% by weight of the particles are in the range from l-4mm.

18. A planting medium as claimed in any preceding claim, characterised in that said expanded vermiculite consists of particles having a size distribution such that at least 80% by weight of the particles are in the range from l-5mm.

19. A planting medium as claimed in claim 18, characterised in that at least 95% by weight of the expanded vermiculite particles are in the range from 1- 5mm.

20. A planting medium as claimed in claim 18 or 19, characterised in that at least 70% by weight of the expanded vermiculite particles are in the range from 2- 3mm .

21. A planting medium as claimed in any preceding claim, characterised in that the medium further includes plant nutrient additives.

22. A planting medium as claimed in claim 21, characterised in that said plant nutrient additives include soluble sources of the elements N, P and K.

23. A planting medium as claimed in claim 22, characterised in the nitrogen is present at least in part as urea.

24 A planting medium as claimed in any preceding claim, characterised in that the medium is in particulate form.

25. A planting medium as claimed in any one of claims 1 to 23, characterised in that the medium is in compacted form.

26. A planting medium as claimed in any one of claims 1 to 23, characterised in that the medium is in packaged form.

27. A planting medium as claimed in claim 25 or 26, characterised in that the planting medium includes a seed.

28. A planting medium as claimed in claim 26, characterised in that the planting medium is contained within an envelope formed of a water-permeable cellulosic material.

29. A planting medium as claimed in claim 28, characterised in that a plurality of said envelopes are joined together to form a sheet or web.

30. A planting medium as claimed in claim 28 or 29, characterised in that said water-permeable cellulosic material is tea bag paper.

31. A planting medium as claimed in claim 28, 29 or 30, characterised in that the or each envelope includes a seed.

32. A planting medium as claimed in claim 31, characterised in that said seed is a pre-germinated seed.

33. A planting medium as claimed in claim 31 or 32, characterised in that said seed is coated with a powdered mineral prior to being incorporated in said envelope.

34. A planting medium as claimed in claim 33, characterised in that said powdered mineral is gypsum or a clay.

35. A planting medium as claimed in claim 33 or 34, characterised in that said powdered mineral includes one or more additives to assist the growth of a plant.

36. A planting medium as claimed in claim 35, characterised in that said one or more additives are selected from growth promoters and pest control agents,

37. A method of growing a plant, which comprises packaging a seed together with a planting medium as claimed in any one of claims 1 to 24 in a water- permeable envelope; and placing the packaged seed at the location where the plant is to grow.

38. A method of planting seeds, which comprises: packaging seeds one by one into individual water- permeable envelopes together with a planting medium as claimed in any one of claims 1 to 24; and placing the packaged seed at the location where the plant is to grow.