CA1328744C - Water retentive matrix incorporating plastic for growing seeds and plants - Google Patents

Abstract

TITLE
WATER RETENTIVE MATRIX INCORPORATING
PLASTIC FOR GROWING SEEDS AND PLANTS
Abstract of the Disclosure There is provided a matrix composition for use in germinating, growing, and protecting a variety of seeds or plants under different conditions. The composition provides protection from predation and mechanical injury, and upon exposure to moisture is converted to a water-retentive, gas-permeable gel which bonds the seed to the ground and establishes a nurturing habitat facilitating plant growth. The composition is of use in forestry and agronomy and for specialty crops. In addition, the matrix may be substituted for conventional potting soil.

Description

` 1 132874~
water Retentive ~atrix Incorporating Plastic for Growing Seeds and Plants .
Technical Field . ~ 5 This invention relates to a water retentive matrix - composition for improving germination rates, retaining water, and, when used as an encapsulating material, for protecting ~eeds from predation and mechanical injury with application in the fields of forestry, agronomy, and commercial and amateur horticulture.
Background of the Invention Currently, the replanting of harvested commercial forest acreage requires labor-intensive planting methods.
Year-old nursery-raised, bare-root tree seedlings are transplanted by hand or semi-mechanized equipment to open - woodlands. This is a costly and time-consuming procedure necessitated by the delicacy of the plants. Light and water needs of bare-root seedlings require very careful handling with specialized environmental controls such as refrigeration or misters to prevent overheating or drying out while in transit. The seedlings are bulky, often become root-bound and have limited periods for transplantation. Survival rates of only 70% are considered the best obtainable with current practices and under optimum conditions.
Other agricultural markets face similar limitations of pre-grown seedlings. Commercial vegetable farming relies on pre-grown seedlings of tomatoes, tobacco, and cabbage. Home gardeners also make heavy use of pre-grown seedlings.
Seeding directly into fields would be preferred in the forestry industry, but to date this has proved ineffective due to the high seed mortality from predation and the lack of predictable moisture and light. A
protective material to encapsulate the seed is a means of protecting the seed from these dangers and of improving germination rates.

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The idea of encapsulating seeds to improve germination i8 known. For instance, U.S. Patent No.
4,628,633 uses compressed peat moss enclosing the seed to absorb water to form a loose, partially light-transmitting structure. Planting is simplified since theencapsulated seeds will dry out less quickly and can be shipped more cheaply and conveniently in less space than pre-grown seedlings. The rounded shape of encapsulated seeds permits bulk handling methods.
However, there are additional qualities not possessed in peat alone that can be achieved by a novel composition of materials. Total mechanization of planting would be possible through use of improved encapsulated seeds. The semi-mechanized planting of bare-root timber seedlings, for example, require a deep-shank plow to plant the seedlings deep enough into the soil. In contrast, encapsulated seeds need a shallow planting depth, which reduce~ the horsepower needed for the machine, increases the speed of the operation, and permits machine planting on otherwise unsuitable sites.
Hand planting, the mo6t expensive method in time and cost, is faster with encapsulated seeds than with bare-root seedlings. Encapsulated seeds are easier to handle -~ and more can be carried by the hand-planter than can - 25 bare-root seedlings. In addition, encapsulated seeds will not dry out as quickly.
Whether planted by machine or by hand, encapsulated seeds do not experience the transplant shock found in bare-root seedlings. Misplanting, resulting in "J"- or "L"-shaped root seedlings which are unable to produce a desirable tree, is eliminated. The better protected encapsulated seed is plantable during a longer window of time, permitting coordination with herbicide application, a cost-savings not now available. However, known matrices have not produced the advantages cited to the degree needed by the industry.

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; 3 An improved matrix for encapsulating seeds is needed to better protect the seed and so to improve germination and survival rates above the industry average of 17%
after twenty-eight days. The improved matrix must reflect a balance between the water absorbance capacity of the encapsulating matrix and it8 structural integrity.
The matrix should accommodate the addition of nutrient~, fungicides, fertilizers and dyes. Under proper conditions, it should permit the aerial planting of seeds. In addition, the matrix may be substituted for conventional potting soil.
Summary of the Invention Applicants' invention is in part a matrix composition for protecting seeds against injury and - 15 enhancing the conditions for germination and growth of ; seed~ and plants. The matrix comprises 55 to 80 percentby dry weight of a hydrophilic fibrous bulking agent, - 0.001 to 0.35 percent by dry welght of a non-ionic - surfactant, ~ to 40 percent by dry weight of a - 20 substantially fully hydrolyzed (90-100%) poly(vinyl alcohol) of a molecular weight between 10,000 and 50,000, water in an amount of between 10 and 25 percent by weight of the composition, and 5 to 20 percent by dry ~ weight of a water retentive polymer with a water ;- 25 absorbtivity of between 50 and 600 times its weight.
- Preferably, Applicants' invention is a matrix composition comprising 73 percent by dry weight of peat, 0.2 to 0.35 percent by dry weight of polyoxypropylene-polyoxyethylene block copolymer, 11 to 13 percent by dry weight of a substantially fully hydrolyzed poly(vinyl alcohol) with a molecular weight of approximately 50,000, and 14 to 16 percent by dry weight of potassium acrylate acrylamide copolymer. Water is added in an amount of 10 to 14 ;`; percent as measured against the dry elements to activate the polymer.
Detailed Description of the Invention ., ';' , ~

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-~ Applicants have invented a water retentive matrix that permits improved germination rates in seedlings and can be used advantageously as a potting soil substitute for plants. The instant invention solves the problems inherent in bare-root seedling transplantation methods described above. The matrix material provides an environment that balances (1) sufficient retention of water in the matrix to sustain the ger~inating seedling and (2) sufficient structural integrity of the matrix to - lo protect the seedling from mechanical injury and predation. The matrix when wetted yields a gel that bonds to the sowing surface, localizing the seedling to grow at that point. The invent~on uses a water soluble polymer, a water retentive polymer in combination with bulking material, and other components described below to achieve the desired protection.
The matrix permits the passage of oxygen to the ; seedling and can include nutrients, dyes, fertilizers, ~ and fungicides. The matrix of the invention can be ; 20 shaped to accommodate a seed of any size for forestry, ; agronomic or horticultural purposes. It is envisioned that Applicants' invention will be used to replant stands - of longleaf pine, slash pine, white pine, red pine, jack pine, spruce, and other commercial tree crops.
Factors influencing the way in which Applicant~' invention is used in the forestry industry include the amount and type of rainfall received in a planting area.
Where rainfall varies from very intense to long drought periods as in the southeastern United States, insertion in a small hole formed in the 80il is preferable. Where rainfall is less intense and more consistent as in the -~ northwestern United States, England and Canada, aerial -~ disper~ion would achieve the greatest cost savings in - labor and ti~e.
Additional important uses for the matrix are with commercial vegetable crops, in the commercial greenhouse trade, and by the significant number of amateur '.
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5 13287~4 gardeners. In particular, i~ is envisioned that the potted house plant market will obtain great benefit from the water retentive properties of the matrix when used as a replacement for conventional potting soil. Used as a ~- 5 potting medium, the matrix will not need watering for up to a full month after initial watering. It releases water over time on an as needed basis helping to prevent over or under watering of the plant.
The components of Applicants~ invention include:
A. Hydrophilic Fibrous Bulking Agent : A hydrophilic fibrous bulking agent forms the ; majority (55 to 80% by weight) of the total matrix.
" Examples of the bulking agent include peat, cotton, r mineral wool, paper pulp, wool and hair. The grind size of the bulking agent i8 important to the matrix retaining its structural integrity even when wet. In its preferred form, the bulking agent is peat that can pass through a 1/8" scre~n.
B. Water S41uble Binder Material ` 20 Substantially fully-hydrolyzed (90-100%) polyvinyl alcohol (PVA~ is the preferred water soluble binder material. The invention requires that whatever water -~ soluble binder material used is soluble in hot water to - solution impregnate the peat or other bulking material, but i~ largely insoluble in cold water to maintain binding of the matrix under field conditions. Cold water soluble PVA would be unacceptable since it would leach from the matrix when wet. The PVA i8 chosen from a broad molecular weight range, so that when wet the PVA
continues to bind the matrix together. A number average for the molecular weight of the water soluble binder i~
approximately 10,000 to 150,000. The PVA is used in an amount of 5 to 40% by dry weight of the total matrix depending on expected climatic conditions. Applicants used approximately 12% PVA (Elvanol~ 7130, E.I. du Pont de Nemour6 and Company). The particular PVA used has a molecular weight of approximately 50,000. Additional ,i . . .

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water soluble binders which can be used in the invention include polyvinyl acetate and polyacrylates.
C. Non-ionic Surfactant Non-ionic surfactant or emulsifier wets the dry hydrophilic bulking agent and allows it to blend with substantially fully-hydrolyzed (PVA) in solution. The surfactant decreases surface tension otherwise preventing water take up and thus increases the rate at which the bulking agent absorbs water. Surfactants include polyoxypropylene-polyoxyethylene block co-polymers:
alkanol amides, betamol derivatives; block copolymers comprising a series of condensates of ethylene oxide with hydrophobic bases formed by condensing propylene oxide with proylene glycol; ethyoxylated compounds comprising `~ 15 alcohols, alkyl phenols, amines and amides, alkylphenol ethoxylates, fatty alcohol polyglycol ethers, oxo-alcohol polyethyleneglycol ethers, alkylphenol-ethoxylate~, fatty or oxo-alcohol polyethylene glycol ethers, and ~- hydrophilic and hydrophobic block copolymers.
Applicant'6 preferred non-ionic surfactant is polyoxypropylene-polyoxyethylene block copolymer (Pluronic L-92, BASF) in an amount of 0.001 to 3.5% by dry weight of the total matrix.
` D. Noisture Content The materials, including the bulking agent, the water coluble polymer, and the non-ionic surfactant, are blended with a roller drum and dried to approximately lO
to 25% moisture content in a 95C air circulating oven.
Moisture content of the matrix at the point of production is a critical feature to maintain the relative qualities of the water soluble material and the water-retentive polymer described below. The amount of water needed to trigger the activation of the water-retentive polymer to sufficiently allow encapsulation was surprisingly small.
The moisture activates the binding agent to form the matrix networ~ which assists in maintaining the structural integrity of the matrix during transport and "

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, - 13287~4 handling. It is understood that climatic conditions after production may affect the moisture content and appropriate packaging may be required to prevent this while the invention is in storage or transit.
E. Water-Retentive Polymer ,.~
Water-retentive polymers, also called superabsorbing polymers or SAP's, are hydrophobic materials which can ~- absorb fluid and retain it under pressure without dissolution in the fluid being absorbed. The materials used are generally all synthesized by one of two routes.
In the fir6t, a water soluble polymer is cross-linked so that it can swell between cros~-links but not dissolve.
;~ In the second, a water-soluble monomer is co-polymerized with a water-insoluble monomer into blocks. The earliest lS superabsorbent materials were saponified starch graft polyacrylonitrile copolymer~. Synthetic superabsorbers include polyacrylic acid, polymaleic anhydride-vinyl monomer superabsorbents, starch-polyacrylic acid grafts, polyacrylonitrile based polymers, cross-linked ~ 20 polyacrylamide, cross-linked sulfonated polystyrene, `- cross-linked n-vinyl pyrrolidone or vinyl pyrrolidone-- acrylamide copolymer, and polyvinyl alcohol superabsorbents.
These polymers absorb many times their own weight in aqueous fluid. The water retentive polymer chosen for seed encapsulation should have a water absorbtivity of between 50 and 600 times its weight. At such absorption levels, the entire composition upon exposure to rainfall is converted to a wet, gas-permeable gel which protects and bonds said seed to the ground during germination.
Additional candidate~ for the water-retentive polymer include sodium propionate-acrylamide, poly(vinyl pyridine~, pclyethylene imine, polyphosphates, poly(ethylene oxide), vinyl alcohol copolymer with acrylamide, and vinyl alcohol copolymer with acrylic acid acrylate.

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-- 132~744 The preferred water-retentive polymer used by Applicants i8 1 to 25% by dry weight of potassium acrylate acrylamide copolymer, preferably in an amount of 13 to 16% by dry weight of the matrix. The material i8 commercially available under the trade mark "Viterra"
from the Nepera Chemical Company.
For~,ation of Compressed Matrix Product The matrix was compressed at room temperature to form a seed encapsulating product. The matrix may be compressed while containing the seed, but this re,~uires a lower pressure to prevent injury to the seed.
Alternatively, the matrix may be pressed at high - pressures (approximately 7500 psi) before the seed is ~ inserted into the matrix unit. The size of the cavity to - 15 hold the seed is determined by the size of the particular seed type used. Once the ,6eed is placed in the cavity, ;~ the cavity opening i8 plugged with a suitable material that will remain in place once dried and that i~ not toxic to the seed or germinating plant. For example, Applicants used a paste composed of 50% by dry weight dry peat and 50% by dry weight of an a,~ueous solution ~` containing 11.25% by dry weight PVA (Elvanol~ 7130, E.I.
du Pont de Nemours and Company) and 0.125% by dry weight non-ionic surfactant (Pluronic L-92, BASF). Other material may be used to plug the cavity including silicate clays.
Functioning of the Encapsulated Seed ~ When the blended material is wetted after seeding by : hand, by machine, or by air, it becomes gel-like, expands, and bonds to the soil localizing the ,6eedling's growth at the point the seed capsule is deposited.
Approximately one inch of rain is re,~uired to activate the preferred capsule matrix: however, water re~uirements - can be varied in light of local climate condition,s, seed re,~uirements, and re~ulting proportions of matrix components. f~he resulting gel-like ~,tructure permits the exchange of oxygen and the retention of water which are ~r 13287~
,.. , g essential for the germination of the seeds. It also ; forms a mechanical barrier to predators. In addition, the encapsulating process per~its the optional inclusion of nutrients, fertilizers and fungicides selected to address local conditions. Applicants have added commercial fungicides such as Benlate~ at levels to 5000 ppm, Ridamil~ at levels to 50 ppm, and Thiaram~ at levels up to 25 ppm to the matrix without toxic effect to the seeds.
Precise ratios of ingredients are important to obtain the most advantagesus characteristics of the matrix. The particular use made of the matrix and local growing conditions will dictate the ratios chosen. Por instance, it is essential that the matrix, when wetted, holds sufficient water to supply the needs of the - germinating seeds, bedding plant, or house plant, but not hold so much to subject the seed or plant to a deleterious a~ount of water. The combination of component characteristics in the matrix yield a product that has qualities of performance, convenience and cost-effectiveness.
EXAMPLES
EXAMPLE 1. Preparation of Encapsulating Matrix.
` Commercial peat moss was dried in an air oven to less than 1% water content, ground in a Wiley mill, and screened through a 1/8" holed screen. Two hundred grams of a distilled water solution containing 15.62 g of poly(vinyl alcohol), (Elvanol~7130, E.I. du Pont de Nemours), and 0.260g of surfactant, polyoxypropylene-polyoxyethylene block copolymer (Pluronic~L-92, ~ASF), were added to 100g of the above dried peat moss and hand ~ blended in a plastic bag. The blend was then placed in - an 85 C oven and dried to a moisture content of between 10 and 25%, as ascertained using an Ohaus Moisture Analyser, Model 6010PC. The moisture content was ascertained but not recorded, since subsequent handling - and storage before seed encapsulation resulted in minor ~ , ,t _ .

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:; 10 changes in the water content. The resulting material was then dry blended in a bag with 14.32 g of the water -~ retentive pol~mer, potassium acrylate acrylamide copolymer (Viterra~, Nepera Chemical Co.). The resulting blend thus had the following dry weight percentages of each component of the total non-aqueous ingredients, by calculation: 12% poly(vinyl alcohol) (Elvanol~ 7130, E.I.
du Pont de Nemours), 0.2% surfactant (Pluronic~ L-92, BASF), 11.0% water retentive polymer (Viterra~, Nepera Chemical Company) and 76.8~ peat.
EXAMPLES 2 to 7 Using the same procedure as in EXAMPLE 1, ~; compositions were made varying the amounts of ingredients ` added to lOOg of dried peat to give the following calculated weight by percent compositions (on a dry basis, as in EXAMPLE 1):

:~ Example ~ Poly(vinyl alc.) Pluron~c L-92 Vit~rra/grade Peat 2 1696 0.2%11/360E 72.89 3 24 0.2 11/360E 64.8 4 24 0.2 5/360E 70.8 24 0.2 16/360E 59.8 6 18 0.2 11/360E 70.8 7 14 0.2 11/360E 74.8 EXAMPLES 8 to 11 These examples use the same procedure as in Example 1, except that in Examples 9 and 11, a small amount of - 30 methyl 1-(butylcarbamoyl)-2-benzimidazolecarbamate fungicide (Benlate~, E.I. du Pont de Nemours) was added at the same time the aqueous solution was added to the - dried peat moss. The following compositions were prepared. Quantities refer to weight percent of total non-aqueous ingredients:

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Example ~ Poly(vin. alc) Pluronic L-92 Vit~rra/ Peat Fungicide grade 8 12 0.27.5/360E 74.8 0 +7.5/375 9 12 0.27.5/360E 74.55.25 : +7.5/375 18 0.211/360E 70.8 0 - 11 18 0.211/360E 70.3 .5 Viterra~ grade 360E ha~ an average grind size of 0.3 mm.
Viterra~ grade 375 has an average grind size of 1 mm.
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EXAMPLES 12 to 19 and EXAMPLE 20. Encapsulation, ~ Greenhouse Germination, and Control.
i In Table I, the matrix number refers to the polymer r 20 from the corresponding matrix preparation examples above.
Table I also indicates the encapsulation procedure and ~ gives the results of germination studies. The .,'',J~ encapsulation method varied depending on whether the seed was inserted within the matrix after (Method A) or before ~, 25 (Method B) pressing. In addition, the germination conditions varied. The germination methods (Methods A, B
and Control) are described below.

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; TA~LE

. -~ LOBLOLLY SEED ENCA~5nLAnON A~l) GE3RMnNAnC~N SllUI)I~

., . ~ NO. OF ll~;r IqRE~iSING WE~rllNG % GE3RMlrlAllON (DAl~S) E3CAJuCPllE # MAll~CY # S~PEC~fEr~S~EiT~iQD M~3C~al2 7 L 21 2 .,. 10 .2 12 1 8 A A O 13 25 38 : . ~ 8 A A 0 25 50 50 . 8 A B 0 25 38 100 ~: 8 A B 13 25 25 75 ^ 8 A B 0 13 ~3 7s 8 A A 0 13 2s 63 8 A A 0 2s 75 88 . 14 3 8 A B 0 50 63 88 8 A A 0 0 2s 88 8 A A 0 2s so 6a :~ 15 4 8 A B 0 38 63 75 8 A 8 0 2s so 75 .~. 8 A B 0 0 38 50 , 8 A A 0 13 25 38 . . ~, ., 35 17 6 8 8 B 0 13 ~3 13 ;, 8 B A 0 S3 63 75 . 8 B A 0 75 75 ;5 18 6 8 C B 0 25 2s 2s 8 C A 0 50 50 so ` . 19 7 8 8 B 0 25 63 75 8 B A 13 63 ~3 63 , (Bare S~##l ~ B 33 41 59 6~
Cont~]) 48 - A 31 63 75 79 . 48 - B 0 38 65 85 -, __ .

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Encapsulation:
Method A. About 4g of matrix was pressed in a conventional platten type compression molding machine at room temperature, using a pressure of 7500 psi per capsule. A cylindrical mold cavity was used resulting in capsule dimensions of 0.5 in. deep and 0.75 in. diameter.
The mold had a concentric stud resulting in a hole in the capsule 5/16 in. deep with a diameter of 3/16 in. The seed was placed in the hole, which was then plugged with ground up peat moistened with surfactant.
Method B. About 2g of peat was placed in the mold and a seed carefully placed as centrally as possible in the mold. About 2 more g of peat was then added to the i mold. The peat and seed were then compressed at room temperature with a pressure of only 263 psi, in order to minimize damage to the seed during encapsulation.
Method C. The same procedure as that described in ` method B was used, except that the pressure was only 188 psi .
Germination:
Method A. Several capsules were wetted in the numbers of specimens indicated by the Table I and placed in a pan on the soil surface and brought to field ` capacity. "Field capacity" refers to the saturation point or the amount of water that the soil will hold at equilibrium. The pans were then covered with a clear - acrylic sheet to maintain field capacity, providing sufficient moisture for encapsulated seeds to germinate.
The pans were then placed in a greenhouse and maintained at 65-75F.
Method B. Several capsules were wetted and placed in a pan on the soil surface. The pans were not covered but were subjected to 0.5 inches of simulated rainfall every other day. This provided sufficient moisture to germinate the encapsulated seeds.
Control method. Bare seeds were placed directly on the soil surface and their germination time recorded.

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Germination data in the accompanying Tables include the number of seeds germinated after the indicated number i of days. Values are given in percentages. Thus 1 out of 8 is shown as 13~; 3 out of 8 as 38%; etc.
The Examples show that capsules allow seeds to grow as well as seeds planted directly. That is to say, the capsules do not have a phytotoxic effect on the seeds.
The data suggest that there may be some damage to the seed resulting in slightly reduced germination when the seed is in place before pressing the capsule. The greenhouse studies described above do not show superiority of the capsule over bare seeds, since this ~; would only be expected under field conditions where predation and other adverse conditions would be expected to adversely affect bare seeds. Such field test are described below.
EXAMPLES 21, 22, and Control EXAMPLE 23.
These examples used the encapsulating Method A as described above. In Table II below, the initial number refers to the matrix of the corresponding matrix preparation examples. The capsules were placed in holes 1.5 inches in diameter and 1.25 inches deep. Germination xi~ studies were carried out in the fall in Buna, Texas.
Data are shown in Table II giving number of specimens and germination after 28 days. Rainfall measured during the period is given. These tests show the superiority in percent germination of the capsules over bare seeds under real growing conditions. They also indicate that the presence of a fungicide further increases the germination rate.

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~; 15 TABLE II
FALL_FIELD TEST DATA
(Buna, Texas) %GERNINATION
EXAMPLE ~ M~TRIX ~ NO . OF SPECIMENS (AFTER 28 DAYS ) - ~ 22 9 50 66 : 23 - 50 36 ( Bare Seed Control ) ., Rainfall during 28 day period = 1.55 inches ;~ 7th day = 1.10 inches 9th day = 0.25 inches ~`~ 25 12th day = 0.10 inches 17th day = 0.10 inches EXAMPLES 24 and Contrcl EXAMPLE 25.
~; 30 Matrix 6 was used in this EXAMPLE 24. This Example :-, ~ used the encapsulating method A described above. The ,, data shown in Table III were obtained from greenhouse - tests. Seeds or capsules were placed on the surface of a sandy loam soil contained in pans with - 35 holes drilled in the bottom. The soil was wetted to field capacity initially. The pans were then placed on ~ rubber sponge pads that were kept saturated with water.
;~ The greenhouse was kept between 65 and 75 deg F and a relative humidity of 45 to 70%.
These tests were designed to show the effects where - only a limited amount of water was present, or the conditions placed the seeds-'under stress.' Once again, the results æXlown in Table III, indicate the clear advantage of lencapsulation.

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TABLE III
GERMINATION DATA FOR LOBLOLLY PINE SEEDS
(Stress Test) GERMINATION
(DAYS) EXAMPLE # MATRIX tNO. OF SPECIMENS 7 14 21 28 24 6 ~2 0 32 57 64 .~ 24 0 25 45 63 : 25 (Bare Seed Control) 72 0 25 25 25 ~ 15 EXAMPLES 26, 27 and 28 s~ These Examples used the encapsulating Method A
`~ described above. In Table IV, the intitial number refers to the matrix of the corresponding matrix preparation ~;, examples. The capsules were placed on the soil surface.
Germination studies were carried out in the spring in Buna, Texas. Data are shown in Table IV giving the ~- number of specimens and germination after 28 days. Total rainfall measured during the period is given. These tests show the superiority in percent germination of the capsules over bare seeds under real growing conditions.
~ They also indicate that the presence of a fungicide - further increases the germination rate.
TABLE IV
Spring Field Test Data ; (Buna, Texas) -: ~ GERMINATION
35EXAMPLE t MATRIX tNO OF SPECIMENS ~AFTER 2~ DAYS~

(wLthout Benlate~) (~ith , Benlate~) - 45(Bare Seed Control) Rainfall during 28 day period - 8.46 inches :, , 17 13287~
EX~MPLE 12 Applicants compressed the following matrix - composition into 2" X 3/8" chip-like wafers with 7500 psi:
12% by dry weight PVA (Elvanol~ 7130, E.I. du Pont de Nemours and Company) 15% by dry weight water retentive polymer (Viterra~, Nepera Chemical Company), 7.5% 360E
grade/7.5% 375 grade -; 10 .35% non-ionic surfactant (Pluronic~ L-92, BASF) 72.65~ hydrophilic bulking agent (peat) .
Sufficient water is added to trigger the water retentive polymer enough to bind the wafer together during production.
The matrix wafers were then moistened to fully activate the water retentive polymer and the resulting matrix used as potting soil in which to plant house plants. The size of the wafer was determined by reference to the standard size flower pot the matrix would expand to fill. Preliminary growing trials were run with squash, watermelon, cantaloupe, bell pepper and ; okra plants over a two month period. No deleterious effects were noted from use of the matrix and water retention of the matrix was considered a convenience and advantage.
A variety of house plants were potted in the matrix ~ including Pathos, Aglaonema, "China Doll", Rex Begonia, - Calathea, Draconia, Diffenbachia, Boston Fern, Aloe, Croton, and "Peace Lily". No deleterious effects from use of the matrix were noted. Comparable specimens of Pathos, Aglaonema, "China Doll", and Rex Begonia were planted in the matrix and in conventional potting soil.
Each was wate,~ed once to saturation at the outset of the trial period imd like species were compared after 20 days (Pathos, Aglaonema) and 10 days ~"China Doll", Rex Begonia~. All of the house plants planted in Applicants' ,, , ~ .

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matrix showed a more healthy appearance than those planted in conventional potting soil. Evidence of advantageous effects included glossier leaves, no wilting, more growth, and no browning of leaves.
Applicants believe that the matrix's ability to release water on an as-needed basis accounts for the superior results of these trials.
It will be apparent that the instant specification and the examples are set forth by way of illustration and lo not limitation, and that various modifications and changes may be made without departing from the spirit and scope of the present invention.

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Claims (13)

1. A matrix composition for protecting seeds against injury and enhancing the conditions for germination and growth of seeds and plants, comprising:
55 to 80 percent by dry weight of a hydrophilic fibrous bulking agent, 0.001 to 0.35 percent by dry weight of a non-ionic surfactant, 5 to 40 percent by dry weight of a substantially fully hydrolyzed (90-100%) polyvinylalcohol of a molecular weight between 10,000 and 150,000, 5 to 20 percent by dry weight of a water-retentive polymer with a water absorbtivity of between 50 and 600 times its weight, and water in an amount of between 10 and 25 percent by weight as measured against all other components of the composition.

2. The composition of Claim 1 wherein the hydrophilic fibrous bulking material is selected from the group consisting of peat, cotton, mineral wool, paperpulp, wool and hair.

3. The composition of Claim 2 wherein the hydrophilic fibrous bulking agent is peat in an amount of between 70 and 75 percent by dry weight of the matrix composition and having a grind size that will pass through a 1/8 inch screen.

4. The composition of Claim 1 wherein the non-ionic surfactant is selected from the group consisting of polyoxypropylene-polyoxyethylene block co-polymers;
alkanol amides, betamol derivatives; block copolymers comprising a series of condensates of ethylene oxide with hydrophobic bases formed by condensing propylene oxide with proylene glycol; ethyoxylated compounds comprising alcohols; alkyl phenols, amines and amides, alkylphenol ethoxylates, fatty alcohol polyglycol ethers, oxo-alcohol polyethyleneglycol ethers.

5. The composition of Claim 4 wherein the non-ionic surfactant is a polyoxypropylene-polyoxyethylene block co-polymer in an amount between 0.001 and 0.35 percent of the composition.

6. The composition of Claim 1 wherein the water retentive polymer is selected from the group consisting of cross-linked poly (acrylamide), cross-linked poly(acrylic acid) copolymers and ionomers, cross-linked poly(ethylene oxide), saponified acrylonitrile grafted starch, cellulose and cellulose derivatives, acrylic acid grafted starch, poly(maleic acid) copolymers, cross-linked poly(vinyl alcohol) and copolymers, potassium acrylate acrylamide co-polymer, vinyl alcohol copolymer with methyl acrylate, vinyl alcohol copolymer with acrylic acid acrylate, vinyl alcohol copolymer with acrylamide, poly(ethylene oxide), poly(vinyl pyrollidone), sulfonated polystyrene, polyphosphates, polyethylene imine, poly(vinyl pyridine) and sodium propionate-acrylamide.

7. The composition of Claim 6 wherein the water retentive polymer is potassium acrylate acrylamide co-polymer in an amount between 14 and 16 percent by dry weight of the matrix composition.

8. The composition of Claim 1 wherein the seed encapsulating matrix optionally comprises a pesticide, a fungicide, a dye, a fertilizer, or nutrient.

9. A composition as in any one of Claims 1, 2, 3, 4, 5, 6, 7 or 8 comprising a seed.

10. A matrix composition for protecting seeds against injury and enhancing the conditions for germination and growth of seeds and plants, preferably comprising the following solids:
73 percent by dry weight of peat;
0.2 to 0.:35 percent by dry weight of polyoxypropylene-polyoxyethylene block co-polymer;

11 to 13 percent by dry weight of a substantially fully hydrolyzed poly(vinyl alcohol) with a molecular weight of approximately 50,000;
14 to 16 percent by dry weight of potassium acrylate acrylamide co-polymer; and water in an amount of between 10 and 11 percent by weight as measured against all other components.
11. The matrix composition of claim 10 optionally comprising a pesticide, a fungicide, or a nutrient.

12. The matrix composition of claim 10 further containing a seed.

13. The matrix composition of claim 12 wherein the seed is a vegetable seed or a tree seed.