CA2734241A1

CA2734241A1 - Bio-organic - zeolitic compound to enhance plant growth in toxic substrates as well as in unpolluted substrates

Info

Publication number: CA2734241A1
Application number: CA 2734241
Authority: CA
Inventors: Peter J. Leggo
Original assignee: BIO-GROW ORGANIC Ltd
Current assignee: BIO-GROW ORGANIC Ltd
Priority date: 2011-03-04
Filing date: 2011-03-04
Publication date: 2012-09-04

Abstract

One aspect of the invention relates to a composed organo-zeolitic mixture for enhancing at least one desirable trait of a plant, such as plant growth and crop quality, when combined with substrate/soil. A further aspect relates to the addition of excess zeolitic tuff to substrate containing the organo-zeolitic mixture, which results in even greater plant growth and crop quality.

Description

Field of the Invention This invention relates to the use of zeolite for enhancing desirable plant traits, such as plant growth and crop quality. In one aspect, the invention relates to the use of an organo-zeolitic mixture and excess zeolitie tuff for enhancing crop size, appearance and taste.

Background In the present inventor's earlier European Patent, No. 1 208 922 131, there is described a method of sustaining plant growth in toxic substrates (soils) polluted with heavy metal elements by combining an organo-zeolitic mixture with the toxic substrate to produce an amended substrate.

The organo-zeolitic mixture is thought to stimulate the activity of nitrifying micro-organisms present in the amended substrate. Ammonium ions, produced by the decomposition of the organic component of the mixture, quickly become loosely bound to the zeolite mineral lattice of the mixture. Microbial oxidation of the ammonium ions then follows which leads to the production of nitrate and protons. Apart from the nitrate being a major plant nutrient, the ensuing proton activity greatly increases the ionic mobility of the soil pore-water.

It was also described that plants, growing in the organo-zeolitic amended substrate, have the ability to differentiate the uptake of chemical elements.
This is thought to be due to the high ionic mobility of the soil porewater, as a result of enhanced nitrification, which allows chemical elements free access to root cells and consequent plant uptake.

Although it was realized by the inventor that an organo-zeolitic mixture could sustain plant growth in toxic substrates (soils) polluted with heavy metal elements, it was not suspected that an organo-zeolitic mixture nor excess zeolitic tuff could enhance other desirable plant traits or be used in unpolluted substrates to enhance plant traits such as growth and crop quality.

Summary of the Invention The present inventor has now discovered that, surprisingly, an organo-zeolitic mixture can enhance at least one desirable trait of a plant, such as plant growth and crop quality, when combined with natural, unpolluted substrate/soil.

It has now also been discovered that with the addition of excess zeolitic tuff, to substrate containing the organo-zeolitic mixture described in the present inventor's earlier European Patent, an increase in nitrification occurs due to the availability of a greater zeolite surface area to collect ammonium ions - thus leading to enhanced plant traits such as even greater plant growth and crop quality.

According to a first aspect of the present invention, there is provided a method of enhancing at least one desirable trait of a plant, said m4od comprising the steps of:
combining an organo-zeolitic mixture with plant growth substrate to provide an amended plant growth substrate; and growing a pant within the amended plant growth substrate such that the plant has the desired trait.

According to a second aspect of the present invention, there is provided a method of enhancing at least one desirable trait of a plant, said i iethod comprising the steps of.
combining an organo-zeolitic mixture and excess zeolitic tuff with plant growth substrate to provide a tuff amended plant growth substrate; and growing a plant within the tuff-amended plant growth substrate such that the plant has the desired trait.

According to a third aspect of the present invention, there is provided a method of preparing an amended plant growth substrate for enhancing at least one desirable trait of a plant, said method comprising the step of combining an organo-zeolitic mixture with plant growth substrate to produce the amended plant growth substrate.

According to a fourth aspect of the present invention, there is provided a method of preparing a tuff-amended plant growth substrate for enhancing at least one desirable trait of a plant, said method comprising the step of containing an organo-zeolitic mixture and excess zeolitic tuff with plant growth substrate to product the tuff-amended plant growth substrate. We have discovered and proved that the cation exchange capacity of the zeolite does not have to be 100 but can be as low as CEC 46.

According to a fifth aspect of the present invention, there is provided a method of preparing an organo-zeolitic mixture for enhancing at least one desirable trait of a plant, said method comprising the step of combining a zeolitic component with an organic component in a ratio of about l volume zeolitic component to about 2 volumes of organic component.

According to a sixth aspect of the present invention, there is provided an amended plant growth substrate for enhancing at least one desirable trait of a plant, said amended plant growth substrate comprising:

the organo-zeolitic mixture prepared according to the fifth aspect combined with plant growth substrate in a ratio of about 1-2 volumes of organo-zeolitic mixture to about five volumes of plant growth substrate.

According to a seventh aspect of the present invention, there is provided a tuff-amended plant growth substrate for enhancing at least one desirable trait of a plant, said tuff-amended plant growth substrate comprising:

the amended plant growth substrate according to the sixth aspect; and excess zeolitic tuff combined with the amended plant growth substrate, wherein the excess zeolitic tuff is of about equal percentage weight to that used in the amended plant growth substrate.

According to an eighth aspect of the present invention, there is provided a plant when grown by a method according to earlier aspect of the invention.

Definitions of the specific embodiments of the invention as claimed hezein follow.
According to a first embodiment of the invention, there is provided a method of preparing a tuff-amended plant growth substrate, said method comprising the steps of:

(1) combining an organ-zeolitic mixture with plant growth substrate to produce an amended plant growth substrate, wherein:

the organo-zeolitic mixture is composted and comprises a zeolitic component and an organic component in a volume ratio of about 1:2, the zeolitic component of the organo-zeolitic mixture is crushed zeolitic tuff with zeolite abundance comprising about 60-90 volume percent of the tuff, and the organic 5 component of the organo-zeolitic mixture is animal manure and/or green plant waste: and the amended plant growth substrate comprises composted organo-zeolitic mixture to substrate in a ratio of about 1:5 volumes in the case of the organic component comprising animal manure, and in a ratio of about 2:5 volumes in the case of the organic component comprising green waste; and (2) combining excess zeolitic tuff with the amended plant growth substrate to provide a tuff-amended plant growth substrate, wherein the excess zeolitic tuff quantity in the tuff-amended plant growth substrate is about 100 weight percent of that used in the organo-zeolitic mixture.

According to a second embodiment of the invention, there is provided a method of growing a plant in a tuff -amended plant growth substrate, said method comprising the steps of:

(1) combining an organo-zeolitic mixture with plant growth substrate to provide an amended plant growth substrate, wherein:

the organo-zeolitic mixture is composted and comprises a zeolitic component and an organic component in a volume ratio of about 1:2, the zeolitic component of the organo-zeolitic mixture is crushed zeolitic tuff with zeolite abundance comprising about 60-90 volume percent of the tufff, and the organic component of the organo-zeolitic mixture is animal manure and/or green plant waste; and the amended plant growth substrate comprises composted organo-zeolitic mixture to substrate in a ratio of about 1:5 volumes in the case of the organic component comprising animal manure, and in a ratio of about 2:5 volumes in the case of the organic component comprising green waste;

(2) combining excess zeolitic tuff with the amended plant growth substrate to provide a tuff-amended plant growth substrate, wherein the excess zeolitic tuff quantity in the tuff-amended plant growth substrate is about 100 weight percent of that used in the organo-zeolitic mixture; and (3) growing a plant within the tuff-amended plant growth substrate.

According to a third embodiment of the invention, there is provided a zeolitic tuff-amended plant growth substrate comprising:

an organo-zeolitic mixture comprising a zeolitic component and an organic component in a volume ratio of about 1:2, the zeolitic component of the organo-zeolitic mixture is crushed zeolitic tuff with zeolite abundance comprising about 60-90 volume percent of the tuff, and the organic component of the organo-zeolitic mixture is animal manure and/or green plant waste;

plant growth substrate in a ratio of about 5 volumes plant growth substrate to I volume organo-zeolitic mixture in the case of the organic component comprising animal manure, and in a ratio of about 5 volumes plant growth substrate to 2 volumes organo-zeolitic mixture in the case of the organic component comprising green waste; and excess zeolitic tuff in a quantity of about 100 weight percent of that used in the organo-zeolitic mixture.

Detailed Description of the Invention Any suitable type of organo-zeolitic mixture can be used and the mixture can be prepared in any suitable way. A suitable organo-zeolitic mixture is described in the specification of European Patent No. 1 208 922 B1, the entire contents of which are incorporated herein by cross-reference.

The zeolitic component of the organo-zeolitic mixture can be crushed zeolitic tuff (natural or synthetic) containing, for example, an abundance of any one or more of the following natural zeolites:- Clinoptilolite-Heulandite, Mordenite, Phillipsite. or Chabazite.

The zeolite abundance preferably comprises about 60-90 volume percent of the tuff.
Ideally, the zeolite should contain less than about 1-2 weight percent sodium as an extra-framework cation; the main extra-framework cations being potassium and calcium.

The organic component of the mixture can be of any suitable origin; for example, animal manure and/or green plant waste. The preferred animal manure is either poultry or pig manure.

The organo-zeolitic mixture preferably comprises about I volume of the zeolitie component (crushed zeolitic tuff) to about 2 volumes of organic component (animal manure and./ or plant waste).

Preferably, the organo-zeolitie mixture is composted. This mixture can be either heap eo_nposted or placed in a temperature-controlled rotating-drum composting machine.
The rotating-drum composting process can produce a usable product in approximately 100 hours of continuous use. On completion of composting, the mixture can be heated to 70 C for 10 hours to kill any harmful pathogens that may be present.

To prepare the amended plant growth substrate, the (composted) mixture can be added to substrate/soil in a ratio of about 1:5 volumes in the case of the organic component comprising poultry or pig manure or cattle manure, or in a ratio of about 2:5 volumes in the case of the organic component comprising green waste.

In the cases where plants need a higher nutrient content, the (composted) organo-zeolitic mixture can be added to the amended plant growth substrate; and an excess quantity of zeolitic tuff can then be added to the amended plant growth substrate to produce the tuff-amended plant growth substrate.

Any suitable quantity of excess zeolitic tuff can be used and the tuff can be the same as described for the zeolitic component. The zeolitic tuff (natural or synthetic) can be crushed and contain, for example, an abundance of any one or more of the following natural zeolites:- Clinoptilolite-Heulandite, Mordenite, Phillip site. or Chabazite. The zeolite abundance preferably comprises about 60-90 volume percent of the tuff.

The excess zeolitie tuff quantity can be about 100 weight percent of that used in the organ-zeolitie mixture. In a well-prepared organo-zeolitic mixture, the zeolitic tuff content per kg of mixture will be in the order of 500 g. Thus, this amount of excess tuff can be added to the amended plant growth substrate to produce the tuff-amended plant growth substrate.

The desirable trait of the plant can relate to growth rate, plant size, and crop size, appearance and taste. The crop can be a root, stalk, leaf, fruit or vegetable.
The plant can be, for example, a tomato, lettuce, cucumber, radish, pepper, or chilli. The plant can be a biofuel crop grown on contaminated land. The growth enhancement trait can occur over a wide range, from grasses to many different species of higher plants.

The plant can be grown in any suitable substrate. Suitable substrates include artificial or naturally occurring substrates (e.g., soil), polluted (e.g., with heavy metals) and unpolluted/clean substrates, as well as mineral-deficient and otherwise impoverished soils.

Specific implementation of the invention will now be described, by way of example, provided for illustrative purposes and not intended to limit the scope of the invention as claimed herein. Any variation in the exemplified compositions and methods which occur to the skilled addressee are intended to fall within the scope of the present invention.

Brief Description of the Figures Figure I Oil Seed Rape (Brassica napus) leaf chemistry, showing an increase in calcium in the plant growing in amended mine waste.

Figure 2 Oil Seed Rape (Brassica napus) leaf chemistry, showing a decrease in copper in the plant grown in amended mine waste, Figure 3 Ossier Willow (Salix viminalis) leaf chemistry, showing an increase in calcium in the plant growing in amended mine waste.

Figure 4 Ossier Willow (Salix viminalls) leaf chemistry, showing an increase in copper in the plant growing in amended mine waste.

Examples 1.P Preparation of the Organo-Zeolitic Mixture The zeolitic component of the organo-zeolitic mixture was a crushed zeolitic tuff containing an abundance of any of the following natural zeolites:-Clinoptilolite-Heulandite, Mordenite, Phillipsite; or Chabazite. The zeolite abundance comprised 60-90 volume percent of the rock, and contained less than 1-2 weight percent sodium as an extra-framework cation.

The organic component of the organo-zeolitic mixture comprised animal manure or green plant waste. The preferred animal manure was poultry or pig manure or cattle manure.

To make the organo-zeolitic mixture, the components were mixed in a ratio of I
volume of zeolitic component to 2 volumes of organic component, being animal manure or plant waste. This mixture was then either heap composted or placed in a temperature-controlled rotating-drum composting machine.

The rotating-drum composting process produced a usable product in approximately 100 hours of continuous use. On completion of composting, the mixture was heated to 70 C for 10 hours to kill any harmful pathogens that may be present.

2. Preparation of the Amended Plant Growth Substrate In order to prepare the amended plant growth substrate, the composted organo-zeolitic mixture was added to soil. The mixture was added to soil in a ratio of 1:5 volumes in the case of the organic component being made with poultry or pig manure or cattle manure, or 2:5 volumes in the case of the organic component being made with green waste.

3. Preparation of the Tuff-Amended Plant Growth Substrate In the cases where plants needed a higher nutrient content, an excess quantity of crushed zeolitic tuff was added to amended plant growth substrate (i.e..
composted organo-zeolitic mixture plus soil). The excess quantity was 100 weight percept of that used in the organ-zeolitic mixture, typically in the order of 500 g. Thus, this amount of excess tuff was added to the organo-zeolitic amended soil (i.e., amended plant growth substrate) to produce the tuff-amended plant growth substrate.

4. Application of the Organo-Zeolitic Mixtures The inventor has found that organo-zeolitic mixtures will substantially increase 5 their nitrate concentration over time. The analysis of aqueous leachates of organo-zeolitic soil substrates, made with mixtures that have matured over five years, are found to have nitrate concentrations in the order of 1000 to 1200 mg per litre with a correspondingly high electrical conductivity of 8000 200 p Siemens per cm Such an electrical conductivity is evidence of extreme ionic mobilization of the soil pore-water which can 10 in some circumstances cause phytotoxicity. It is therefore recommended, for the treatment of clean soils, to use an organo-zeolitic mixture during the growing season in which it was prepared. In the case of polluted soils, more mature mixtures can be used.

5. Evidence from Plant Trials The growth behaviour of many different plant species, in organo-zeolitic amended unpolluted soil, has now been examined and, with the exception of several leguminous plants, all have exhibited growth enhancement relative to plants growing in untreated soil.
In all cases, water has been used to maintain moist soil conditions.

6. Tomato Growth Trial Tomatoes (Solanum Ailsa Craig) were grown in 4 kg substrates under greenhouse conditions, and replicated three times.

Substrate compositions were as follows:
1. Natural, clean soil.

2. Same soil as I but amended with organo-zeolitic mixture in a ratio of 1:5 (amended plant growth substrate).

3. Same as the amended plant growth substrate of 2 but further amended with 100 weight percept excess zeolitic tuff (tuff-amended plant growth substrate ).

4. Same soil as 1 but amended with Miracle-GroTM, a liquid inorganic plant fertilizer which was applied, as recommended by the manufacturer, every seven days.

The substrates were kept moist by watering with de-ionized water only and the fruit was harvested, when ripe, over a period of two months.

The final yields for each group were as follows:
Plants grown in Substrate 1 ..........................138.14 g Plants grown in Substrate 2 ....................... 1,627.519 Plants grown in Substrate 3 .......................1,788.04 g Plants grown in Substrate 4 .......................1,592.70 g Weight percentage differences in fruit yield relative to the yield of plants grown in the unamended soil control, Substrate 1:

Plants grown in Substrate 2 ..................... 1,078 wt %
Plants grown in Substrate 3 ..................... 1,194 Art %
Plants grown in Substrate 4 ..................... 1,053 ,,l %

This trial demonstrated that the plants grown in Substrate 3 produced 13.39 wt %
more fruit than those grown in Substrate 4.

The difference in the appearance and flavour of fruit from these two groups was clearly evident. Those from plants grown in the organo-zeolitic amended substrate had a scarlet red colour with greatly enhanced flavour. Whereas those grown in soil treated with Miracle-GroTM produced a larger size, pink fruit having an apparent increase in water content.

7. Lettuce Growth Trial Lettuce was grown under glass in two 10 m2 plots. 70 plants were used per plot with one plot, Substrate 1, comprising tuff-amended plant growth substrate as described above, and Substrate 2, comprising natural, clean soil dressed with a mixture of wood shavings and horse dung.

Substrate. 1 was watered regularly and Substrate 2 was watered with an aqueous solution of inorganic fertilizer at the same regular interval as Substrate 1.

At harvest, 20 plants were sampled diagonally across the plots and the fresh weights recorded for each plant.

Plants growing in Substrate 1 had a yield of 5.08 kg with an average weight of 250 g.

Plants growing in Substrate 2 had a yield of 4.78 kg with an average weight of 239 g.

This trial demonstrated that the plants growing in the tuff amended plant growth substrate produced a 6.28 wt % greater yield.

8. Spring Wheat Growth Trial A series of laboratory plant growth experiments were conducted with Spring Wheat (Triticum aestivum L., cv. Red Fife) in unpolluted soil that have shown similar growth enhancement features to plants grown in amended mine waste. By the comparison of plants grown in different substrates, it was clear that those grown in soil amended with the organ-zeolitic mixture increased the dry weight of plants relative to those grown in untreated soil by some 85 wt %. Changes were also very apparent as plants grown in the untreated soil quickly developed leaves with a yellow-green colouration indicating signs of early senescence whereas those grown in the organo-zeolitic amended soil had a dark green glaucous appearance. Clearly marked contrasts in morphology became obvious as the plants reached maturity as those growing in the untreated soil had long slender stems supporting few leaves and a single tiller plant whereas those growing in the amended soil had steps supporting, on average, three to four tillers and a smaller. less dense root structure. These differences were reflected in the dry weights of the grain yields; plants grown in the amended soil having an increase of 117 wt % relative to plants growing in untreated garden soil. Plants growing in soil treated with solutions of 6 mM
ammonium chloride and 6 mM potassium nitrate, to simulate treatment by inorganic plant fertilizer, had smaller grain yield increases of 115 and 140 wt % respectively.

Hypothesis to explain the differential uptake of plant nutrients It has been found by experiment that by amending a soil with the organo-zeolitic mixture, soil nitrifying microbes are greatly stimulated which leads to an enhanced population. This occurs due to the availability of ammonium ions, derived from the decomposition of the organic component, becoming adsorbed on the zeolite surface. In a soil environment these ions are directly available for oxidation by ammonium oxidizing micro-organisms. This reaction produces nitrite ions which quickly become oxidized by nitrite oxidizers to nitrate ions. These reactions also produce protons that dissociate cations from the soil particles which, together with the nitrate ions, are directly available for plant uptake. The effect of nitrification will continue as long as the organic component provides ammonium ions from its decomposition.

Recent studies have shown that the most readily decomposed nitrogenous molecules produce an early supply of ammonium ions that are converted in the first 30 to 40 days from the time of soil amendment. In the case of decomposition of animal waste, these molecules are either urea or uric acid. in time more complex molecules such as amino acids and proteins undergo decomposition and supply ammonium ions which, although not as copious a supply as those first liberated, provide enough nitrate and proton activity to sustain plant growth and sustainability of plants, over several seasons, growing on amended mine waste.

Comparative studies of leaf chemistry of plants grown in clean soil, mine waste and amended mine waste have shown that the plants have a strong tendency to balance their uptake of essential and beneficial chemical elements during growth. The measurement of twenty-one elements has shown that in 80-90% of the cases the plants growing in the amended waste will wither increase or decrease the uptake of an element to approach that found in plants growing in the clean soil. It appears that this differential uptake accounts for the enhancement of growth and quality of plants growing in organo-zeolitic amended soils. From work on metal polluted soils it has been seen that plants, growing in an organ-zeolitic amended substrate, have the ability to differentiate the uptake of chemical elements. This is thought to be due to the high ionic mobility of the soil porewater, as a result of enhanced nitrification, which allows chemical elements free access to root cells and consequent plant uptake. As a result of a series of experiments with plants growing in metal polluted soils, it has been found that a balance appears to be achieved in the uptake of nutrient elements that leads to maximum growth. In the case of edible fruits and vegetables, grown in unpolluted soils, it appears that an enhanced quality of taste results from the use of the amendment. This latter property has been found, subjectively, by tasting the tomato grown using inorganic synthetic fertilizer with those grown in an organo-zeolitic soil system. Using the variety Ailsa Craig it was found that tomato grown with inorganic fertilizer (Miracle-GroTM) had large pink fruit with a high water content and little taste. Plants grown in the organo-zeolitic amended soil had smaller, bright red fruit, with a strong tomato taste. Similar results showing growth enhancement and improved quality have been seen with lettuce, cucumber, radish, pepper and chilli.

This new technology can also be used for the growth of biofuel crops on contaminated land. In this case, growth performance will depend on plant type.
In the case of non-leguminous plants it has been found that the growth enhancement feature occurs over a wide range from grasses to many different species of higher plants.

9. Uptake Trends in Amended Metal Contaminated Soils In the case of Brassica napus, the uptake trends are as follows:

Elements showing an increase in concentration are Boron. Calcium, Potassium, Magnesium, Molybdenum and Sodium.

Elements showing a decrease in concentration are Aluminium, Cadmium, Cobalt, Caesium, Copper, Iron, Nickel, Phosphorus, Lead, Sulphur, Silicon and Zinc.

Arsenic, Manganese and Strontium show anomalous trends.

The following figures show element concentration in leaf tissue plotted against the plant substrate and are typical of the uptake trends mentioned above. The substrates involved are: S.1 garden soil; S.2 mine waste; and S3 amended mine waste.

Figure 1 Oil Seed Rape (Brassica napus) leaf chemistry, showing an increase in calcium in the plant growing in the amended mine waste.

Figure 2 Oil Seed Rape (Brassica napus) leaf chemistry, showing a decrease in copper in the plant growing in the amended mine waste.

} In the case of Salix viminalis the uptake trends are as follows:

Elements showing an increase in concentration are Ca, Cd, Cu, K, Mn, Mo, P. S, Sr, and 7.n.

Elements showing a decrease in concentration are Al, As, B, Co, Fe, Na, Ni, Pb and Si.

10 Both Cs and Mg show anomalous trends.

The following figures also show uptake trends in plants growing in identical substrates as those above.

Figure 3 Ossier Willow (Salix vinzinalis) leaf chemistry, showing an increase in calcium in the plant growing in the amended mine waste.

15 Figure 4 Ossier Willow (Salix viminalis) leaf chemistry, showing an increase in copper in the plant growing in the amended mine waste.

Conclusions It has been clearly demonstrated that organo-zeolitic amended soil enhances desirable plant traits, such as growth. Further improvement in growth and crop quality can be achieved by adding excess untreated zeolitic tuff to the organo-zeolitic mixture amended soil. The excess tuff required is preferably 100 w-t % of that used in the initial mixture but the amendment to soil ratio remains the same, i.e. I part amendment to 5 parts soil.

Although it has been work on metal polluted sites that has shown how plants balance their uptake, it is believed that plants grown in clean soils will respond in the same way. Further, it is thought that plants grown in amended clean soil will balance their uptake in such a way as to increase growth and improve fruit quality.

The experimental evidence herein shows that the modified mixture, when combined with substratelsoil, greatly enhances desirable plant traits, in terms of growth and quality of crops, vegetables and fruits.

Whilst the above has been given by way of illustrative example of invention, many modifications and variations may be made thereto by persons skilled in the art without departing from the broad scope and ambit of the invention as herein set forth.

The term "comprise" and variants of the term such as "comprises" or "comprising" are used herein to denote the inclusion of a stated integer or stated integers but not to exclude any other integer or any other integers, unless in the context or usage an exclusive interpretation of the term is required.

Any reference to publications cited in this specification is not an admission that the disclosures constitute common general knowledge in Australia or elsewhere.

Claims

1. A method of preparing a tuff-amended plant growth substrate, said method comprising the steps of:

(1) combining an organo-zeolitic mixture with plant growth substrate to produce an amended plant growth substrate, wherein:

the organo-zeolitic mixture is composted and comprises a zeolitic component and an organic component in a volume ratio of about 1:2, the zeolitic component of the organo-zeolitic mixture is crushed zeolitic tuff with zeolite abundance comprising about 60-90 volume percent of the tuff, and the organic component of the organo-zeolitic mixture is animal manure and/or green plant waste; and the amended plant growth substrate comprises composted organo-zeolitic mixture to substrate in a ratio of about 1:5 volumes in the case of the organic component comprising animal manure, and in a ratio of about 2:5 volumes in the case of the organic component comprising green waste; and (2) combining excess zeolitic tuff with the amended plant growth substrate to provide a tuff-amended plant growth substrate, wherein the excess zeolitic tuff quantity in the tuff-amended plant growth substrate is about 100 weight percent of that used in the organo-zeolitic mixture.

(2) combining excess zeolitic tuff with the amended plant growth substrate to provide a tuff-amended plant growth substrate, wherein the excess zeolitic tuff quantity in the tuff-amended plant growth substrate is about 100 weight percent of that used in the organo-zeolitic mixture.

2. A method of growing a plant in a tuff-amended plant growth substrate, said method comprising the steps of:

(1) combining an organo-zeolitic mixture with plant growth substrate to provide an amended plant growth substrate, wherein:

the organo-zeolitic mixture is composted and comprises a zeolitic component and an organic component in a volume ratio of about 1:2, the zeolitic component of the organo-zeolitic mixture is crushed zeolitic tuff with zeolite abundance comprising about 60-90 volume percent of the tuff, and the organic component of the organo-zeolitic mixture is animal manure and/or green plant waste; and the amended plant growth substrate comprises composted organo-zeolitic mixture to substrate in a ratio of about 1:5 volumes in the case of the organic component comprising animal manure, and in a ratio of about 2:5 volumes in the case of the organic component comprising green waste;

(2) combining excess zeolitic tuff with the amended plant growth substrate to provide a tuff-amended plant growth substrate, wherein the excess zeolitic tuff quantity in the tuff-amended plant growth substrate is about 100 weight percent of that used in the organo-zeolitic mixture; and (3) growing a plant within the tuff-amended plant growth substrate.

3. The method of claim 1 or claim 2, wherein the zeolitic tuff content per kg of said organo-zeolitic mixture is in the order of 500 g.

4. The method of any one of claims 1 to 3, wherein the substrate is polluted soil.

5. The method of any one of claims 1 to 3, wherein the substrate is non-polluted soil.

6. The method of any one of claims 1 to 5, wherein the zeolitic tuff per content per kg of said organo-zeolitic mixture is in the order of 500 g.

7. Zeolitic tuff-amended plant growth substrate comprising:

an organo-zeolitic mixture comprising a zeolitic component and an organic component in a volume ratio of about 1:2, the zeolitic component of the organo-zeolitic mixture is crushed zeolitic tuff with zeolite abundance comprising about 60-90 volume percent of the tuff, and the organic component of the organo-zeolitic mixture is animal manure and/or green plant waste;

plant growth substrate in a ratio of about 5 volumes plant growth substrate to 1 volume organo-zeolitic mixture in the case of the organic component comprising animal manure, and in a ratio of about 5 volumes plant growth substrate to 2 volumes organo-zeolitic mixture in the case of the organic component comprising green waste; and excess zeolitic tuff in a quantity of about 100 weight percent of that used in the organo-zeolitic mixture.

8. The zeolitic tuff-amended plant growth substrate of claim 7, wherein the substrate is polluted soil.

9. The zeolitic tuff-amended plant growth substrate of claim 7, wherein the substrate is non-polluted soil.

10. The zeolitic tuff-amended plant growth substrate of any one of claims 7 to 9, wherein the zeolitic tuff per content per kg of said organo-zeolitic mixture is in the order of 500 g.

11. A tuff-amended plant growth substrate when prepared by the method of any one of claims 1 and 3 to 6.

12. A plant or crop or part thereof when grown by the method of any one of claims 2 to 6.

13. A plant or crop or part thereof when grown in the zeolitic tuff-amended plant growth substrate of any one of claims 7 to 10.

14. A method of growing a plant as defined in claim 2 and substantially as described in at least one of the accompanying examples.

15. A method of preparing a tuff-amended plant growth substrate as defined in claim 1 and substantially as described in at least one of the accompanying examples.

16. A zeolitic tuff-amended plant growth substrate substantially as described in at least one of the accompanying examples.

17. A zeolitic tuff with a CEC range of 46 to 100 plus.