I would like to thank the following people for their help and encouragement:

Pete Dunleavy provided invaluable assistance with experimentation and hints on writing/ editing this report.

Moria and Cameroon Thomson for information that was vital in the initial stages of research

My Parents for their financial and emotional support while living at home.

My Sister for her editing and English expertise

Karen Knowler for her continued moral support

Mr Barrie Oldfield for advice on experimentation and information on his excellent work at The Men of the Trees in Australia.

Natures First Law for their initial inspiration and advice on diet that has helped me sustain a positive mind and body throughout

Joanna Campe (Remineralise the earth) for her crucial research packet detailing rock dust research from around the world and help with editing via email.

Lance Edwards for encouragement and inspiration

Pinetum Products for the provision of the rock dust.

The main aims of this report were to give an overview of the topic of Soil Remineralisation, to carry out experiments to establish the effects of rock dust on plant growth and to provide a stimulus for further research.

This report brings together information on the topic of Soil Remineralisation. Soil Remineralisation is a concept that treats the soil as a live organism. Finely ground rock dust is added to the soil, which is broken down by microbiological activity. This is said to create food for the plants, which take up the processed minerals from the microorganisms. The plants grown on mineralised soils are then claimed to be healthier at a cellular level. The dust is also said to help bind up excess atmospheric CO² in both plant biomass and by chemical reaction. It is also claimed that the active weathering of the dust is closely related to the glacial cycles of the planet.

The second section of the report focussed on the experiments. Two sets of experiments were carried out with lettuce and cress to establish the effectiveness of a 'mixed volcanic rock dust'. The experiments were carried out in perlite and compost with the lettuce. The cress experiments were carried out on perlite alone.

The growth of the lettuce in the dusted perlite medium showed a significant improvement over the control. The cress shoot height, root length and weight showed a significant improvement for the dusted cress over the control. The results for lettuce in the compost medium were not significantly different over time, however the average height of the control was the best suggesting that the rock dust may inhibit plant growth in the short term in rich soil mediums. The initial growth rate of all the plants was improved in the rock dust treated pots.

These results led to the main conclusion that Soil Remineralisation has potential in biologically orientated agriculture. The final section recommends possible further research that are needed to utilise the potential of Soil Remineralisation

This dissertation will focus on the topic of Soil Remineralisation. The concept of Soil Remineralisation is the process of "loading up the soil with crushed and pulverized rocks which restore the full spectrum of mineral elements. The soil microbes, earthworms and plant roots are directly nourished by an abundance of minerals". (Wolfe1999).

When the Earth is looked on as a whole it is in constant cycles, from the weather to the rocks. The rocks are ground down by glaciers, rivers and weathering and eventually end up deep within the earth's soil mantle. This rock forms fine particles which are ingested by microorganisms to form protoplasm. The plants then take up this protoplasm, which provides the minerals and nutrients for health. (Weaver pers comm 1999)

The world's soils are rapidly being depleted by deforestation, industrialization and poor farming/ forestry techniques. The soils have become depleted and acidic and therefore trees and plants are dying. This leads to rising CO² levels and consequently climate changes. If soils were healthier it would make sense that plants, animals and humans and the planet will thus be healthier. The natural process of mineralisation can achieve this. This can be seen in the simple diagram in Figure 1 below.

Section one of this dissertation provides a detailed background to the topic of Soil Remineralisation. Chapter 1 gives a history of Soil Remineralisation. It discusses the main proponents, and the way the movement has developed today. Chapter 2 looks at glaciation theory, Environmental sustainability and benefits related to Soil Remineralisation. Chapter 3 introduces rock dust and why it is important for healthy soil systems and Chapter 4 looks at the requirements of plants from a Soil Remineralisation perspective. Finally, Chapter 5 mentions some of the past and present scientific research to give an overview of the work that has been carried out within the topic of Soil Remineralisation.

Section two focuses on various experiments carried out by the author and the subsequent results and discussion.

Section three outlines the further recommendation of the author i.e. future research, potential, challenges and conclusions from findings. Personal opinions are also drawn as a result of the findings.

The main aims of this report are to provide an overview of Soil Remineralisation, to carry out experiments looking at the effectiveness of rock dust, and to provide a stimulus for further long-term research into Soil Remineralisation.

This chapter gives a brief history of Soil Remineralisation beginning with the early pioneers and progressing to the present day advocates.

One of the earliest pioneers of Soil Remineralisation was Julius Hensel (1894). Hensel's(1894) work condemned traditional NPK agriculture as being unnatural and dangerous. Hensel (1894) took issue with Justus Von Liebig (1894) who disagreed with the humus theory. He made a scientific case that plants required mineral elements from the soil, carbon from CO2 in the air, and H and O2 from water. (Barak 1995). Some advocates in the remineralisation movement believe this theory to be untrue stating that plants do take up minerals in organic form (Weaver pers comm. 1999). Since the time of Liebig (1894) agricultural research has progressed, investigating the complete requirements of plants, and knowledge today is much more comprehensive. (More details in Chapter 6.0)

Since the contribution of Hensel (1889), research has continued in Soil Remineralisation. Many scientists have done work in both agriculture and forestry in Germany and Central Europe since the 1930's with positive findings (Campe 1995). Work however has been slow. One of the main reasons that work has not been done was because of the lack of technology available to produce finely ground dust. Another reason is because of the lack of funding available, as research has been predominantly focused on chemical agriculture. (Tompkins and Bird 1987)

Thirty years ago, remineralisation was revived in Central Europe and many, rock dust distributors have been established in America, Germany, Austria, Switzerland and a small number in the UK. Recent researchers include Peter von Fragstein (1987) at the University of Kessel, who carried out experiments with various rock dust types as slow release fertilisers and as a means of deterring insects. (Campe 1995)

In 1971, Albert Carter Savage (1971) wrote a report for Acres USA titled "Mineralisation, a new basis for proper Nutrition". Savage (1971), in the 1930's, discovered a balanced concoction based on the simplest of rocks. These rocks included Devonian oil shale, potash marl, secondary fossiliferous limestone and raw rock phosphate. These, in combination with manure or compost, provided an excellent fertiliser for the soil and improved the health of those that ate the food from it. (Walters 1995)

At a similar time, John Hamaker (1982) was writing research papers culminating in his book The Survival of Civilisation based on intensive research into climate. In his book co-written by Don Weaver, he stressed the importance of Soil Remineralisation for restoring soils and forests claiming even more importantly that it was vital for stabilising the climate (see Chapter 3).

The Hamaker movement began soon after he started writing and bloomed in the 1980's after the publication of his book. His work was brave in its conclusions, stating that earth demineralisation was leading to a new glacial period. To provide information, Joanna Campe set up Soil Remineralisation, A Network Newsletter in 1986 that became Remineralise the Earth Journal in 1991. This magazine has provided a backbone for the movement collecting, research and results from farmers and individuals around the world (Campe1995).

A more recent development as stated by Campe (1995) is Agrogeology (see Schreier et al 1991 for details), which is research that has been carried out on laterite soils in Brazil, Canada, Tanzania, the Canary Islands, and West Africa. On these soils, NPK fertilisers are quickly lost in a matter of weeks. Rock fertilisers release nutrients over a long period of time to cultivated plants and also improve the ion-exchange capacity of the soil by forming new, clay minerals during weathering.

Today universities are actively researching Soil Remineralisation, research centres devoted to rock dust research and developing more natural framing techniques e.g. The SEER Centre and Men of The Trees (Appendix E)

In conclusion, examination of this history shows that even though Soil Remineralisation is a fringe topic it continues to be researched.

The next chapter looks at some of the theories behind remineralisation and the potential benefits for the environment and health.

GLACIATION THEORY

The concept of Soil Remineralisation is based on the theory that rock dust is the original ingredient for soil formation provides the earth limited supply. This supply is created by glaciation and weathering which breaks down the rocks and blows the dust around the earth. Walters (1991) states that this occurs in cycles that can be seen as glacial-interglacial. The minerals are said to control these cycles. These cycles are also related to the amount of carbon in the atmosphere, which is in turn linked to the biomass in the plants. As the earth is de-mineralised the plants begin to die and carbon dioxide (CO2) builds up in the atmosphere creating climate instability.

This build up of CO2 is natural, but is being rapidly accelerated due to poor agricultural techniques, deforestation and industry. The content of CO2 within the atmosphere is rising. During the past 150,000 years it has oscillated between 200 & 300ppm. This has risen rapidly since 1959 from 315ppm to 350ppm. Therefore the rate of CO2 build up is many times greater then previous rates. (Supkow 1996)

This rise in CO2 is often talked about and commonly attributed to the "Greenhouse Effect". The Hamaker (1982) theory disputes the global warming theory and claims through his research, the climate is heading for a new Ice Age (See Figure 2 and Appendix C (Survival in the balance). (Weaver pers comm 1999, Thomson 1995)

Hamaker (1982) looked at the data from ice cores and pollen studies and deemed that glaciation occurs in natural cycles. Each interglacial appears to be 10,000 years long with the glacial period being 90,000 years. (Hamaker 1982) In 1991 Nature reported on evidence from arctic ice cores showing a net accumulation of 2,000 km3 a year. The article also claims that sea levels are actually falling as compared to the common consensus of sea level rise (Morgan, Goodwin, Etheridge and Wookey 1991). Thus proving that the global warming theory is not so clearly delineated or that it is warming that eventually triggers glaciation.

There are two important factors to this theory: carbon dioxide in the atmosphere and the minerals in the soil. Combined it is claimed these factors are rapidly bringing forth a new period of glaciation by the process explained below. (Thomson pers comm and Weaver pers comm)

The process (Appendix E Ice age cycle)

The theory states that during glaciation, the massive sheets of ice flowing over the face of the earth grind up tons of rock to dust and gravel. This is deposited wherever the ice has been. Dust storms (Walters 1991) then carry the minerals around the earth. This dust is said to contain all the necessary minerals to support life when combined with the gases in the air and water (see Appendix A for a typical rock dust breakdown). (Weaver 1982)

Each period of glaciation appears to leave a 10,000-year supply of minerals which feed the soil microorganisms and thus the plants and animals (Thomson pers comm 1998, Tompkins and Bird 1986). Hamaker (1982) cites a number of scientific papers that discuss the steady acidification of the soils over the 10,000-year interglacial. These soils are unable to support trees and crops as the minerals are used up. This is beginning to occur around the world, in combination with acid rain. (Hamaker 1982) An example of major climate change is the El Niño effect is now occurring much more often.

This climate change caused by the rising CO2 levels is accelerating the natural greenhouse effect. This is more pronounced in the tropics, due to the higher temperatures, which greatly increases the evaporation. There will therefore, be a temperature difference between the Tropics and the Polar Regions. The greenhouse effect will be much weaker in the Polar Regions, especially during the long, cold dark winters when little sunlight reaches these places at all. (Weaver 1997) The increase of cold polar air, will flow into the tropics, which in turn will force the warm tropical air over the higher latitudes forming a dense cloud cover leading to great storms. This increased cloud cover will reflect more light back into space. The overall effect of increased C02 will be a lower average world temperature. With colder weather and more snow in the high latitudes the great ice sheets will start to increase, leading to a cycle of continual cooling (Alexander 1982: Cited from Hamaker) and eventual glaciation for the cycle to begin again.

Environmental sustainability and slowing glaciation

The Hamaker (1982) theory states that by setting up a world wide programme of remineralisation of soils and forests and tree planting, new glaciation can at least be slowed down if not stopped altogether (see Figure 3, Weaver 1998). This would lock up the excess C02 from the atmosphere. There are various factors that control the atmospheric CO2 levels. After rigorous mathematical calculations however Berner (1991), showed that the primary control factor is the rate of weathering of silicate rocks such as granite, basalt, gneiss and extrusive volcanic rocks (Supkow). These silicate rocks contain a significant amount

of Calcium and Magnesium, which combine with atmospheric C02 to form calcium carbonate and magnesium carbonate. This is often deposited in the oceans as limestone and dolomite, being returned ultimately in the form of volcanic eruptions. Since it is the silicate rocks that weather and remove the C02, this implies that the quicker weathering occurs, the faster C02 is removed from the atmosphere.

Berner (1991) also reinforces the Hamaker (1982) theory, that weathering, increases over geological time. The sustainable solution according to Hamaker (1982) and Supkov (1991) is to accelerate this natural process of weathering by adding finely ground rock to the soil. This is more sustainable than it first appears. In the USA alone the aggregate industry produces 200 million tons of finely ground rock dust. (Fryer 1998) Much of this quarry waste are put in to landfill every year (USDA 1998), which is transported from site or left in spoil heaps.

The feasibility to distribute vast quantities of soil for remineralisation has to be questioned. Even if it could eliminate chemical fertilisation there are still the problems of logging companies, industry and transporting the dust world wide. (Collins 1995) It could provide an important key to creating a more sustainable world, by helping to trap excess CO2, bind up chemicals, create healthier soils and counter the effects of acidification. These benefits are discussed in the next section.

World-wide benefits/ potential

By adding rock dust as a complete plant fertiliser along with plant matter, the soil may be much healthier. Collins (1995) details the potential benefits to the soil as follows.

1. Rock dusts contain most of the nutrients essential for growth except Nitrogen and Phosphorous. (Fragstein 1987)
2. The release of nutrients is directly related to weathering. Consequently, their beneficial effect could last for many years before needing replacement, and even longer if used in conjunction with sustainable farming techniques. The problem of nutrient leaching is minimised as plants take up the nutrients at the same rate as they are being released and there is also minimal problem with toxicity from oversupply of nutrients.(Fragstein 1987)
3. Soil water holding capacity and cation exchange capacity are improved (Fragstein 1987, Lampkin)
4. Some dusts raise pH, countering the effects of soil acidity often found in certain soils.

If the soil is healthier then the plants will be healthier. Mixed rock dust can provide a full spectrum of minerals to the soil and Olarsch (1993) stated that this improves cellular structure, which could explain why rock dusted plants are more resistant to insect attack and disease.

Thus if the plants are more balanced and healthier then it could lead to the conclusion that animals and humans further up the food chain will thus be healthier. It has been noted (SEER 1998) that the use of rock dust can reduce (or even replace) fertilisers, pesticides, fungicides and herbicides.

Potential uses

Soil Remineralisation has various potential benefits outside of feeding the soil below are a few which have been researched:

In 1995 Campe wrote posed the question: "is it possible to speed up the transition time from chemical farming to organic with SR?" In this paper Campe (1995) reports on an independent laboratory that used treated fields that had a 30 year history of pesticide use with a blend of naturally mined, paramagnetic minerals highly charged with energies and combined with beneficial bacteria. Usually pesticides can be detected years after their use on fields, but when the potatoes on this site were analysed, after only one cropping, for 50 pesticides none could be detected.

A great deal of work been carried out in America by the USDA (1998) into the potential to re-use industrial by-products as agricultural amendments. This has multiple benefits such as:

1. Reducing the use of chemicals (fertilisers, pesticides etc) and thus their manufacture, distribution and the pollution that comes with them.
2. Reducing the spoil heaps from quarries
3. Bind up the excess CO2 in the atmosphere and thus help to stabilise the climate
4. Reuse of the waste from industries

Improve the quality of poor soils Rock dust builds the soil (Tompson pers comm. 1998) so the potential for rebuilding dying soils is there if used in combination with compost dying soils could be regenerated. Tropical soils that are low in humus could be, rebuilt from a base of rock dust, which is the basis for Agrogeology.

At the SEER centre (Appendix G) in Scotland much work is been carried out into co-utilisation of rock dust and compost. It appears that when the rock dust is added to compost it not only increases mineral content but also accelerates microbial activity, heat build up, and therefore the rate of break down. It is also said that toxicity is reduced. The SAC have recently begun a program of research into this to explore the potential for community run projects.

In the next chapter the report investigates the best types of rock dust recommended for Soil Remineralisation.

Rocks are the basis by which soil is formed and this chapter looks at the most suitable rock types for remineralisation. Soil is a living thing made up of solid, liquid and gas and also the important soil organisms/ microorganisms. These organisms breakdown plant/ animal matter to create soil humus, a rich organic matter which provides for the plant requirements. (CPRE 1998)

The rock types that are used for Soil Remineralisation are the keys to the health of the plants. Some of the world's richest soils are found in valley flood plains and mountain areas. Examples of these are the Nile Valley which was maintained by annual flood borne deposits of silt, prior to the building of the Aswan Dam, and the fertility of volcanic ash soils in parts of Indonesia (Coleman 1985, Coroneos 1994, Campe pers comm. 1999).

The ideal rocks therefore would appear to be glacial moraine materials because these are rocks that have been formed deep within the earth from a large variety of rock elements (Walters 1991). These rocks form mountains by geomorphic processes and are subsequently ground down by glacial action into a mineral rich material. This material contains a large range of rock types and particle sizes.

In natural conditions this process takes hundreds of thousands of years. By artificially grinding the rocks down it is possible to accelerate the, natural cycles. There are various definitions of rock dust but in general it should contain a high percentage of particles less than 75 microns (Fragstein and Vogtman 1987). This is important because it provides a large surface area of rock to be rapidly broken down by the microorganisms that are said to prepare the minerals for the plants in a usable form (Hamaker 1982). Some elements are not however provided, such as Nitrogen and Phosphorous as mentioned earlier, which only occurs in small amounts. These are however provided in a healthy balanced soil system.

Type of Rocks Igneous rocks appear to have the best results and the most researched are the basalts. Suitable basalt rocks include Bentonite, Serpentine, Feldspar, Pumice's and Green-sand. (Hamaker 1982, Oldfield 1999 pers comm, Collins 1985) the breakdown of which is illustrated in Table 1.

The size of the particles is a key component of a healthy soil system. The importance of this can be clearly seen when a soil profile is examined (Figure 4) which shows range of particle sizes. Soils that are less mature contain a larger proportion of large rock particles and as these are broken down by the action of plants, weathering and organisms, they mature into fertile nutrient rich soils. (Cooper 1975)

From the above profile it can be seen that to create a rich soil, a range of particle sizes are required. The finer particles will provide instant feed for the microorganisms while the larger will provide a more long-term release of minerals.

These particles are broken down by the microorganisms and taken up whole in the form of protoplasm. (See Chapter 5) The smaller the particles, the greater the surface area is exposed. More minerals are therefore available for the soil microorganisms. It has been estimated that 0,45 kg of finely ground gravel produces 4 hectares of surface area available for breakdown (Wolfe 1999). The more efficient rocks are however not just determined by the total content of minerals but by their availability (Collins 1995)

This chapter shows the importance of finely ground volcanic rock to provide quality base fertiliser for the building of soil systems.

In the next chapter the report builds on the information on the rock types and looks how they are utilised with the microorganisms by the plants for nourishment.

The views held by remineralisation writers differ significantly from conventional science. In this section the report looks in detail at the claims made by the remineralisation movement.

Liebig (1884) carried out experiments to establish what contributed to plant growth. By burning a plant it was discovered in the ash that Nitrogen, Phosphorous and Potassium were present in substantial amounts and from this it was (Liebig 1884) deemed that these wholly nourished the plants. (Thompson and Bird 1987 and Barak 1995)

This discovery fuelled the development of synthetic chemicals without further investigation. Since the work of Liebig (1889) much experimentation into essential mineral elements has been carried out.

Science is beginning to realise that plants require a much broader spectrum of elements. Marschner (1986) established the following criteria for essential elements:

1. A given plant must be unable to complete its life cycle in the absence of the mineral element.
2. The function of the element must not be replaceable by another mineral element.
3. The element must be directly involved in plant metabolism.

Korcak (1996) states that "Sixteen elements are considered to be essential for the growth of higher plants. These include those required in relatively large amounts. (1% dry weight or more) ie H,O,N,C,K,Mg,P,S, and CL and those required in relatively small amounts (ppm) levels ie Mn, Zn, Cu, Fe, B and, Mo" Most of these are provided by rock dust (Appendix A) and from the environment in healthy soil systems.

These elements must be provided by the soil and differ for each plant and each situation depending on the various interactions within the soil. When chemicals are added they can cause imbalances in the soil that can thus be injurious to the plants (Cooper 1975, Hensel 1885)

"There are many problems with chemical fertilisers as they can destroy the natural soil environment Petrochemical fertilisers are often high in soluble salts that are detrimental to soil microbes and plants alike; they decrease microbial activity and plant nutrient uptake". (Enviro-guard 1999)

The best way therefore to nourish the soil is holistically as nature does. This means helping to create a balanced whole live system i.e. humus, organisms, microorganisms and minerals. Agriculture today is limited because it is becoming more and more dependent on synthetic chemicals to feed the crops and protect them against insects and disease. Therefore there is less focus on building healthy soil systems.

To create a healthy soil it is important to look in terms of feeding the soil with a broad spectrum of minerals, which in turn feeds the plants. The source of these minerals as recommended by the remineralisation advocates, as mentioned in chapter 4, is igneous rock dust. This addition of ground rock to the soil is where the idea of remineralisation is based. A large spectrum of minerals is fed to the soil along with the input of waste plant matter, without the use of chemicals. The soil organisms will then help to create a healthy balanced environment. (Thompson pers Comm. 1998)

This may well be true, but sceptics will question how can plants take up whole organic minerals. Conventional science teaches that plants can only take up minerals in the form of solution taking the minerals directly by osmosis (Hissinger et al 1996).

The remineralisation stance is that if "plants can take up whole molecules of chemicals, insecticides etc and therefore there is little reason to doubt, that they can take up minerals in chelated or complex form" (Acres USA 1983, Fryer 1998). A key point to note is that the root systems are considerably larger in remineralised plants an example of which was seen by Edwards (1980) in trials with Banana plants.

Weaver (1998) and others (Hamaker 1982, Hensel 1880, Tompkins & Bird 1989, Fragstein 1987) believe that plants take minerals up directly in the form of protoplasm This is the process as described by Weaver (1998). "Rock dust feeds the soil, i.e. the worms and soil microbes, the essential minerals they require to build protoplasm and enzymes and the mineralised microbes as digested by the plant roots to nourish the plants. In the discussion a study is mentioned where protoplasm was recorded being ingested directly by the plants. In the diagram on the next page (Figure 5: Bretcher (1987) demonstrates how plant cytoplasm directly ingests large particles.

"Micro-organisms produce the protoplasm of all living things. Microorganisms themselves feed on the total mixture of minerals and gases in the biosphere and are energised by carbon. It is possible to build large per acre tons of protoplasm into the soil in a very short time - enough so that sun energy reaching the plant becomes the limit of growth. The foods of micro-organisms are the cheapest raw materials of the earth," (Hamaker 1982).

These are some of the claims made by the remineralisation advocates. There are few arguments for or against as there has been little peer reviewed scientific research done on Soil Remineralisation (Szmidt 1998) The next chapter looks at some of that work which has been carried out.

This section gives a brief overview of some of the work that has been carried out into Soil Remineralisation, with the main focus on agriculture. Much work has also been carried out in forestry some examples being Men of the Trees (Appendix G), who are using Granite dust with tree seedlings and

The North Carolina state University who are carrying out trials on a, mountain forests where trees are dying of acid rain (Collins 1995)

Scientific work has been carried out in Europe, notably Germany and Austria on Agriculture (Collins 1995). Fragstein v P, Pertl and Vogtmann (1983) carried out much research in Germany into the potential of silicate rock as natural fertilisers, examining their weathering properties and the qualitative and quantitative aspects of their use. Their main conclusions were that rock dust has potential when used in conjunction with natural biologically orientated agriculture. In the short term, however, it is unable to compete with soluble fertilisers for uptake. (Fragstein 1983)

There has also been some research done into the potential of using dust on tropical soils where nutrient losses are great, especially with traditional soluble NPK fertilisers (Leonardos, O. H., 1985). Schreier, Matheis & Kamlage (1991) researched Agrogeology as a chance for West Africa's Food-Production and there is similar work to help tropical countries improve food production to replenish minor nutrients and trace elements (Chesworth et al 1983, Gillman 1980).

The United States Department of Agriculture (USDA 1998) is currently researching by-product utilisation, by reclaiming materials such as quarry waste fines, gypsum and coal dust. They can be combined and composted with municipal by-products. This composting reduces pathogens, toxins and odours to create high quality natural fertilisers for the soil. This has great potential for the problem of landfill (USDA 1998)

Within the United Kingdom (UK) the research is progressing, but slowly. The soils in the UK are of a high quality due in part to the fact that UK was, covered by glaciers thousands of years ago providing the basis for high quality soils. Also for the UK was mainly covered in trees which helped to stabilise the soil. This however is changing as the UK is facing the following problems (CPRE 1998)

1. Wind erosion - In flat drier eastern parts of the country large areas of farmland are losing topsoil.
2. Open cast mining - Over the last 10 years almost 23,500 hectares have been approved for open cast coal mining.
3. Urban development - The current rate of loss is too high and is restricting the choices about the use of land available to future generations. At current rates a fifth of England will be urbanised by 2050.
4. Water erosion - This occurs on ploughed slopes, where hedgerows have been removed where arable cropping is continuous and where fields are irrigated.
5. Loss of organic matter - The main causes include over intensive use of the soil by agriculture, the ploughing up of grasslands, and the loss of traditional crop rotation.
6. Nutrient enrichment - This is a result of over-application of nitrates and phosphates from inorganic fertilisers, sewage sludge and manures. These can then leach into watercourses.
7. Soil acidification - This is exacerbated by emissions of acidifying gases from industry and agriculture. Acidification can cause metallic leaching restricting plant growth and causing freshwater pollution.
8. Poor farming practices - Poor land management is encouraged by inappropriate farm subsidies.

Inline with these problems the Government is preparing the first ever Soil Protection Strategy to take better care of the soil resource of the British countryside (CPRE). Could Soil Remineralisation be part of the solution to regenerate British soils? In the field of Soil Remineralisation there is some work being research work being carried out in Scotland at Universities and Colleges.

The Sustainable Ecological Earth Regeneration (SEER 1998) Centre Trust has been influential in much of the work in Scotland. SEER is an organisation that is actively campaigning for more research into Soil Remineralisation as they believe that it could be part of the solution to a sustainable future. They have written a 5 year project plan (outlined in Figure 23) to research Soil Creation and Soil Remineralisation with aims to address climate change, waste minimisation and sustainable organic agriculture. The Scottish

Agricultural College (Appendix G) is working closely with SEER, and is planning research into the potential of co-utilising rock dust and composted material. Glasgow University is also researching the role of microorganisms on the leaching of silicate rocks.

 In Australia there has been research into the potential of rock dust (Granite) as a source of potassium compared to soluble fertiliser. The results showed reasonable uptake but not as good as soluble fertilisers (Coronenos 1994). Also in Australia, there has been work into the effect of silicate rock powder on selected chemical properties of a range of soils from Western Australia (Hissinger et al 1996)

Much of the work into Soil Remineralisation is anecdotal evidence from avid followers therefore there is little peer reviewed literature available. This work is important, as it provides the stimulus for further work. If however Soil Remineralisation is to be accepted in the mainstream more scientific research needs to be carried out.

All the research from around the world is being collated by Remineralise the Earth (Appendix G) as a central point of information for rock dust research.

In the next section the report details the experiments carried out by the author looking at the potential of rock dust as a fertiliser.

1. What are the effects of rock dust on the plants?
2. How does rock dust effects the growth rate of plants?
3. Does rock dust improve plants growth?
4. Does rock dust have any negative effects on plants growth?
5. Does the effect change when more dust is added?
6. Does rock dust have any effect in compost?
7. How does rock dust effects root length, shoot and weight of the plants?

To attain these objectives, Perlite and John Innes compost were used alone to compare the effects of rock dust on nutrient poor and nutrient rich soil. The first chapter in this section looks at the methods used in these experiments.

This chapter includes information on how the rock dust was prepared, the planting procedures and the computer analysis that was carried out on the raw data.

Rock Dust Preparation

In preparation for the rock dust experiments the rock dust was obtained from Pinetum products (1998 see Appendix G). Pinetum products also sent an independent ICP - MS Analysis (see Appendix A) of their mixed volcanic rock dust.

The dust was then graded to establish the range of particle sizes that it contained. The dust was dried and graded in an automatic sieve shaker for fifteen minutes. (Table 2)

For the experiments five replicate pots were used of the following compositions of medium and volcanic rock dust.

To achieve equal proportions of dust in the pots it was added by 5% and 10% volume. This dust was sprinkled onto the pots after filling with the potting medium and mixed.

15 pots with filled with perlite and 15 with compost.. To which were added 5% dust to 5 perlite and 5 compost pots and Added 10% dust to 5 perlite and 5 compost pots

Then the Little Gem lettuce seeds were sprinkled into each pot and water was added. The pots were randomly mixed in a tray and covered in the potting shed for three days to allow sprouting.

The pots were then uncovered and moved into the green house. On each visit the positions were changed to provide equal conditions for all the plants.

The shoot height and general health of the lettuce was recorded every two days, when the plants were watered with 250ml of water.

The Cress experiments were carried out to provide a more detailed analysis looking at root, shoot length and the weight of the plants. It was decided for such a short-term experiment to further grind the dust, using a pestle and mortar, to create a finer consistency and only use dust below 2mm. The grading of the altered dust is as follows:

The results for the lettuce and the cress were the inputted into Stat-view analysis program and a Factorial ANOVA Analysis was calculated, the results of which can be seen in the next section.

This chapter displays the results that were obtained from the experiments carried out during the summer of 1998. First the lettuce results are displayed followed by the cress. The results are described as to what they are showing, following this section the discussion examines about these results in more detail.

Lettuce

 Figure 6: Lettuce Summary graph comparing the various growing mediums

In this graph (Figure 6) we can see the clear comparison between the treatment methods

Perlite: There is an apparent difference between the perlite medium, which rises as more rock dust is added. The difference is more pronounced between the control perlite and dusted perlite, than the 5% and 10% dusted. With the dusted lettuce the initial growth rate was slightly faster.

Compost: Comparing the compost treatments, the lettuce with dust has a much faster initial growth rate. After about two weeks the growth rates level out somewhat and 5% dust actually taking over for a time. By four and half weeks the treatments have levelled out and are almost equal.

Lettuce - Perlite/ Compost

Figure 7 shows a standard growth curve. This growth occurs within the first two weeks and then the growth levels out with a rise in week five. At this point the experiments were ended as the plants had outgrown their pots. When removing the plants from the pots it was noticed that the dusted pots had a greater root system although no record was made of this, but it was recorded in the following cress experiments.

Figure 8 compares the mean height against treatment methods. In this figure the compost control is significantly twice that of the perlite control. There is only a slight difference between the 5% dusted compost and the 5% dusted perlite, the compost being the greater., however the 5% dusted compost is 30% less than the non dusted compost. With the 10% added dust the results are improved the compost is almost the same as the non-dusted compost. The dusted perlite is only 10% lower than the dusted compost.

Figure 7 Combination of results for date for perlite and compost mediums

Figure 7 compares the mean height of all the samples combined over the sampling period with reference to date.

Table.6 shows the numbers sampled on each date, the mean height for the combined compost and perlite, the standard deviation and the standard error.

Figure 8 shows the comparison between the methods of treatment for both perlite and compost. Table 7 shows the significant difference for methods of treatment/ date and both combined. Table 8 shows the number of samples, mean heights, standard deviation/ error for the various treatment methods.

Figure 9 shows the growth rate rising significantly in the initial two weeks after which it falls and then continues to rise again for the next three weeks to an equal height to that reached in the first week alone.

Figure 10 shows significant 25 % rise in height of the lettuce from no dust to 5% dust and a further 14% rise to 10% dust.

Figure 9 compares the mean heights for the perlite alone related to date of harvest. Giving a clear picture of the perlite growth rates.

Table 9 shows the number of samples, mean heights for each date, standard deviation and standard error.

Figure 10 clearly shows the growth rate comparison for perlite control with 5% dust and with 10% dust.

The table below (10) shows the significant difference between treatment/ date and both combined. Table 11 shows the results for the perlite control, 5% and 10% dust, displaying samples taken, mean height standard deviation and error.

Figure 11 shows a steep rise in height after the first week after which it levels out with a peak and then a fall in the last week. The changes in height for the date are not significant and neither is the combination of treatment and date.

Figure 12 shows a significant fall from the control to the 5% dust of 34%. The 10% dust is slightly less than the control.

Figure 11 compares the mean heights for the perlite alone related to date of harvest. Giving a clear picture of the perlite growth rates. Table 12 shows the number of samples, mean heights for each date, standard deviation and standard error.

Figure 12 clearly shows the growth rate comparison for perlite control with 5% dust and with 10% dust.

The table below (13) shows the significant difference between treatment, date and both combined.

Table 14 shows the results for the perlite control, 5% and 10% dust, displaying samples taken, mean height standard deviation and error.

Table 14: Treatment comparisons comparing figures from stat-view

b) CRESS

Cress - 8^th October

The following section details the results for experiments completed in October 1998comparing dusted and control samples in perlite growing medium.

Root Length (Figure 13)

The length of the root is significantly different for dusted and control samples. The dusted sample is twice the mean length of the control.

Shoot Height (Figure 14)

The mean heights of the cress shoots are significantly different between the dusted and control samples. The dusted samples are approximately 20% greater then the control.

Weight (Figure 15)

There is no significant differences between the weights of dusted and control samples.

Figure 13 shows the mean root length comparison between the rock dusted treated cress and the control cress. Table 15 is the data from stat view showing the significant difference between them. Table 16 shows the count of samples, mean height, standard error and deviation.

Figure 14 shows the mean root length comparison between the rock dusted treated cress and the control cress.

Table 17 is the data from stat view showing the significant difference between them. Table 18 shows the count of samples, mean height, standard error and deviation.

Figure 15 shows the mean root length comparison between the rock dusted treated cress and the control cress.

Table 14 is the data from stat view showing the significant difference between them. Table 15 shows the count of samples, mean height, standard error and deviation.

Root Length (Figure 16)

There is a significant difference between dusted and control samples for the length of root. The mean length for the dusted samples is twice that of the control.

Shoot Length (Figure 17)

There is a significant difference between the dusted and control samples for the shoot length. The mean shoot length is more than twice that for the dusted as the control.

Weight (figure 18)

There is a significant difference between the weight of the dusted and control samples. The dusted is approximately twice that of the control.

Figure 16 shows the mean root length comparison between the rock dusted treated cress and the control cress.

Table 21 is the data from stat view showing the significant difference between them. Table 22 shows the count of samples, mean height, standard error and deviation.

Figure 17 shows the mean root length comparison between the rock dusted treated cress and the control cress. Table 23 is the data from stat view showing the significant difference between them. Table 24 shows the count of samples, mean height, standard error and deviation.

Figure 18 shows the mean root length comparison between the rock dusted treated cress and the control cress. Table 25 is the data from stat view showing the significant difference between them. Table 26 shows the count of samples, mean height, standard error and deviation.

Introduction

This discussion looks at the above results. It attempts to establish the differences found between the dusted and the control samples and discusses some of possible reasons for these results. In the first section it discusses the lettuce experiments and on page 42 the cress experiments are discussed.

LETTUCE - INITIAL IMPRESSION

The main aim of these experiments was to establish whether rock dust actually had an effect on plant growth. The results show outstandingly that growth was greatly improved, as can be seen in the results.

The experiments (Figure 19) show that the plants with added rock dust have increased growth when compared to the controls. The effect of a higher percentage of dust on the lettuce also had a growth advantage. This was more pronounced in the perlite samples than the compost samples. (See below),

Compost (Figure 20).

COMPARING PERLITE AND COMPOST - FOR CONTROL, 5% AND 10% ADDED DUST

In the first set of results (Figure 6 & 8) the individual treatments were compared for both compost and perlite. The fact that compost control height was greater than the perlite control was to be expected. This is because the perlite is chemically inert adding nothing in the way of nutrition to the plants (Appendix D), and has limited water holding capacity when compared to the compost, which is nutrient rich and has better water holding capacity.

When comparing the compost (+5% Dust) and perlite (+5% Dust) the results were interesting in that they were very similar in height (Figure 8 page 29). This suggests that the rock dust provided all the nutrition necessary for growth. If it had been significantly less it may have suggested that the rock dust only improved the quality of the medium for growth such as the water holding capacity. In comparing the compost (+10% Dust) and the perlite (+10% Dust) the results vary by 10% (Figure 8 page 29). This suggests that the compost also improved by the addition of rock dust. The fact that the perlite was only 10% less than the compost is also of interest in that it shows that possibly the dust was providing adequate nutrition for growth.

COMPARING THE INDIVIDUAL MEDIUMS

The perlite results were very interesting (Figure 9). The analysis shows a higher initial growth rate which, can be seen for both the 5% and 10% dusted perlite. This suggests that the rock dust was either providing, much needed early nutrients for the plants or that possibly the water-holding capacity of the medium was improved or cation exchange capacity was improved.

After the third week the results stabilise and there is a definite difference between the three sets of results. Approximately 10mm (mean) between the control and 5% dust and 5mm (mean) between the 5% and 10% over time suggesting a sustained growth rate. The rock dust did not inhibit growth relative to the amount of rock dust added.

The treatment comparison (Figure 10) shows very clearly that the increase in rock dust concentration from 0 to 5 to 10% has quite a significant effect. The 5% dust was 10mm (mean) higher than the control and the 10% dusted samples were a further 6mm (mean) higher. These results suggest that the rock dust is more effective with greater quantity, possibly due to the fact that more fine particles are available for uptake via the microorganisms.

The results also show that the addition of more rock dust does not have a toxicity effect on the growth of plants because this would inhibit growth. Korcak (1996) suggests that oversupply of essential and non-essential nutrients could create phyto-toxicity in plants. This is countered by some of the rock dust proponents who claim that rock dust does not feed the plants, but rather the microorganisms, bacteria and worms. The plants then readily select the nutrients they require rather than forced osmosis from solution fertilisers (Hamaker 1982, Thompson and Bird 1986, Hensel 1894)

The date comparison (Figure 20) as with the perlite shows an early growth spurt for both the 5% and 10% compost when compared to the control. This continues until the third week when the control reaches equal height. This suggests that crops with early nutrient demands would benefit from rock dust application.

The 5% dust continued to grow after the third week, as does the control. The 10% dusted lettuce, height actually falls a little and then jumps again. After the fifth week they are all very close in heights. These results show that with the compost and dust over time for lettuce, the growth rate was not significantly improved.

The comparison of treatments (Figure 12) proves much more interesting than the date comparison because the average height for the compost actually falls from the control to the 5% dust. This is partly because two pots of the 5% samples failed to survive possibly due to over watering. The pots that did survive were as healthy as the control and 10% dust. If the results are studied as they stand there could be a few reasons for this lower height.

Firstly that the dust could be inhibiting growth by providing too many nutrients as suggested by Korcak (1996). This is also hinted at by the death of two pots. This was not however noticed in the 10% dusted pots.

Secondly no measurements were taken to assess the health at a cellular level. According to Olarsch, (1993) if plants are allowed a full spectrum of trace elements cellular structures are strengthened. The only evidence of this is when the plants were removed from the pots It was noted that the root growth was much more pronounced in the dusted pots for both compost and perlite samples. This has been noticed by many proponents (Thompson, Edwards pers comm. 1998) of rock dust who imply that the roots are actively searching for minerals due to the enhanced microbiological activity. (Hamaker 1982, Tompkins and Bird 1986)

The 10% dusted sample shows a better result when compared to the 5% dust. The average height was not significantly less than the control. This implies that adding rock dust to high quality soils is not worthwhile in the short term. However over the long term it is suggested that the minerals are released gradually in tune with the plant requirements. (Fragstein 1987)

The 10% dusted samples are better than the 5% dusted samples, which suggests that more dust increases the rate of growth. The fact that the compost, control is the best of all shows that adding rock dust to mineral rich soil possibly hinders rather than helps growth, which could be due to over enrichment of the soil.

These results prove that rock dust when added to the growing medium has an overall positive effect on plant growth, especially in poorer soils. This is concluded in the final chapter. In the next section the cress results are discussed.

CRESS

Figure 21: Weight comparison related to date and Figure 22 Shoot/ root comparison related to date and

treatment treatment

The cress experiments were carried out to give a more detailed picture of what occurred when rock dust was added. This was achieved by measuring the root/ shoot length and weighing each random sample. The cress was harvested twice over a period of two weeks. First the discussion will focus on the individual harvests and then compare the two together.

The results for the root length show an almost 50% increase in length. (Figure 13) This suggests that the rock dust stimulate root growth. This could be due to the increased microbiological activity, which is claimed to occur when rock dust is added to the plant medium. (Gray 1995)

The roots that were in the rock dusted pots also appeared to have an increased amount of root hairs suggesting that they were taking up the rock dust particles Weaver (pers comm 1999) relates studies done using photomicrography, the uptake has been observed in the form of protoplasm.

The length of the shoot was also significantly greater than that of the control (Figure 14). This implies that the possible uptake of minerals as suggested above produced more growth. The length of the shoot was 20% greater and in general healthier than the control plant. Cress does not however demand much nutrition in the early stages so the extra growth could be the fact that water-holding capacity was improved by the addition of rock dust. Next the cress was weighed to establish if there was an increase in biomass.

The mean weight was not significantly different, although it was greater in the dusted cress (Figure 15). Could the addition of rock dust have increased the biomass or was this just an anomaly in the results?

On the 16th of October a 55% difference in mean root length between the dust and control treatment were seen (Figure 16). This implies that the addition of rock dust, was having an effect on the root development confirming the idea that addition of rock dust increases microbiological activity and thus stimulates root development.

The shoot length (Figure 17) was very much the same being 59% greater, which is quite a large difference. The possible reasons for this are mentioned earlier.

The weight (Figure 18) at this time was significantly different by 50%, this implies an increased biomass in the plant and links closely with the fact that the root and shoot lengths were greater.

Looking at the figures (Figure 21/22) there is a significant difference between the dates which should be obvious. This however is much clearer with the dusted cress. The root length jumps up 22% between the harvest dates for the dusted cress whereas the control remains stable. The shoot length is 52% greater in the second week compared to no change for the control. Figure 21 it shows a 48% increase in the weight by the second week while again the control remains the same.

When the experiments were carried out the possibility of error was considered? The main being in measuring the lettuce and taking an average height for each pot, this was made more difficult by the fact that the lettuce became drawn due to been kept in pots and thus drooped over. There was also the anomaly of the 5% dusted compost (Lettuce) when two pots died. In the next section recommendations will be made for the future of rock dust experiments both relating to these experiments in particular and further more detailed experiments.

In the final section of this report all the findings are drawn together in the conclusion.

Soil Remineralisation is a vast topic and to give a complete overview in such a short report was perhaps over ambitious. The author however feels that the report covers the main aspects of Soil Remineralisation. This was important to do because the information that is available on Soil Remineralisation is somewhat limited. Bringing this information and newer information together the author has created a report that can be used as a basis for further work.

Often when Soil Remineralisation is mentioned, it is believed that it only involves adding rock dust to the soil. This however is only part of the topic. Soil Remineralisation is another way of looking at nourishing the soils and taking care of them for future generations.

The soils are the basis for all of life on the Planet Earth (Figure 23). If it were not for the soils then Earth would be a bare lifeless rock. The very essence of life is contained within the soil, therefore they need to be treated as living organisms.

Once the soils are healthier then the plants that grow on them will be healthier chemical use can be reduced and thus the soil humus can be rebuilt. The author believes that Soil Remineralisation is only part of the solution. To create a healthier and more sustainable way of living Soil Remineralisation needs to be used in conjunction with the following:

1. Global tree planting to reduce rising CO2 levels
2. Permacultre techniques that work in harmony with the land
3. Environmentally sensitive building, transportation and ways of living/ working
4. To eat in accordance with our biological needs (Wolfe 1999) thus reducing our dependence on highly processed foods and stimulants.

These may seem irrelevant in such a report, however the author feels that everything relates to everything else and to create a truly sustainable future everything needs to be looked at holistically.

The original aims of this report were:

1. To give an overview of the Soil Remineralisation.
2. To carry out experiments to confirm the findings of advocates from around the world.
3. To create stimuli for further research and collate information and recommendations.

1) Soil Remineralisation is a vast topic and very controversial in that it goes against current scientific thinking, due to the variety of claims made by the advocates. It is clear however from writing this report that these claims are being proved to be correct as more research is being carried out. The main conclusions that the author has found from this report are as follows:

• Soil Remineralisation is only part of the solution.
• Rock dust has potential for plant growth, planetary stabilisation and animal/human health.
• Rock dust can help to rebuild soils that have been degraded by poor land management.
• Soil remineralisation works best using mixed dusts.
• Advocates around the world have successfully used soil Remineralisation.
• Research within the laboratory has limited results due to the fact that there are a variety of complex interactions in the soil environment.
• The most suitable rocks are mixed glacial material and ground finely to feed the microorganisms.
• That global warming is only part of the picture and we could in fact be heading for glaciation.

2) The second section of the report focussed on the experiments carried out by the author in the summer of 1998. The experiments showed outstandingly that rock dust improved growth especially in the initial stages of both compost and perlite mediums. The results showed that rock dust was better in the perlite mediums in both cress and lettuce. This shows that rock dust has great potential for the initial rebuilding of degraded and poor quality soils. The results in the compost were not as good proving that in high quality soils the potential of rock dust may not be required. This is obvious and shows that if farmers were to take better care of the soils by adding back what is taken out in the form of plant matter, and utilising less intensive agricultural practices then there would be no need for soil remineralisation. The fact remains that much of the worlds soils are rapidly being degraded and soil remineralisation could help in the initial stages to rebuild the soil.

3. To provide stimulus for further research. Hopefully the work contained within this report will provide a stimulus for further research. This is achieved by the following:

1. Collation of current information and thinking
2. Listing of organisations from around the world
3. Listing of internet links
4. This report will be distributed via the internet (See Appendix G) and sent to the various remineralisation organisations around the world

Doing this the means that the information can firstly be critically assessed and secondly that it will provide a basis for future research. In the next chapter the report looks at some of the possibilities for the future research.

The main limitation of this report was the lack of scientific literature. This section provides a list, with ideas, of some recommended further experiments and ideas for wider detailed research.

1. Record of root growth - The growth of the roots within remineralised plants has been noticed in many experiments. Further detailed recording of root length at different stages of growth, number of root hairs and photographs.
2. Mineral analysis of plants compared to added rock - The mineral analysis of the plants on the completion to growth to compare the mineral content to the minerals available in the soil and to control samples. This would enable availability of the rock dusts to be established.
3. Longer-term experiments to allow full plant development - The experiments were limited in that the plants were restricted to pots, therefore their growth was stunted. Complete growth over a longer time period would allow more detailed results.
4. Further research on the same soil to establish the long-term effects - This would be useful to establish whether the microbiological activity broke down further minerals for plant uptake on a long term basis compared to control.
5. Pre-prepare the soil to allow microbial activity - It would be interesting to pre-prepare with an innoculant of microorganisms the soil to assess the microbiological activity.
6. Measurement of the number microorganisms - A comparison between the dusted and control pots to see if adding dust stimulates microbiological activity
7. Measurement of organic matter in soils - It would be interesting to compare the organic matter in dusted and control samples.

1. Long term experiments - These need to be carried out to assess the longer term effects of rock dust on plant growth
2. Focused research into glaciation - The theory of glaciation as promoted by Hamaker (1982) needs further detailed research.
3. The effect of various parameters: Different dust grades - How do different grades of dust effect the soil and plant uptake. Mixtures of dusts -Research is required to establish the best rock mixtures for both plants and soil types. Different climates - How do different climates effect the microbial activity and nutrient uptake. Different plants - Do some plants react better to rock dust? Are some plants effected negatively by rock dust applications? Are there better mixtures for different plants?
4. Research into the role of microorganisms - The role of microorganisms is a major topic in Soil Remineralisation. Intensive research needs to be carried out to establish their role and their link with the roots. Do the plants attract microorganisms suitable for their needs? Do the plants actively take up minerals? If so how? What part do microorganisms play in a balanced soil system?
5. Feasibility of distribution - Is large-scale distribution of rock dust a feasibility? Do the negative effects of transport counter the positive effects of chemical use reduction/ elimination, climate stabilisation
6. Research into optimum soil conditions for plant health at a cellular level - What is the optimum soil conditions to create the healthiest plants at a deep cellular level.
7. How are plants effected at a cellular level - The effect of cellular strength is commented upon. How is it effected by the addition of rock dust? Is the resistance to disease and pests increased by the addition of rock dust? If so, is this due to the increased cellular strength?
8. Research into the effect of binding up toxins present within the soil - Can the addition of rock dust possibly bind up toxins? Could it be used in conjunction with bio-remediation techniques?
9. How can remineralised plants be better for health - The heath of remineralised plants is often associated with an improvement in bodily health. Could the improved plant structure effect human health.
10. Can rock dust provide a soil builder for regeneration of poor, degraded or toxic soils - The soils in the UK and world-wide have been degraded. Can Soil Remineralisation provide a sustainable alternative to regenerate and rebuild these soils?
11. Research into methods of grinding the dust - The ideal dust is ground finely, methods of grinding this dust in the simplest way possible.

These are just a few of the recommendations for further research. The field of Soil Remineralisation has potential but if extended detailed research is not carried out then potential is all it will ever have.

Total Element Concentrations (Micrograms per gram (PPM))

Perlite is not a trade name but a generic term for naturally occurring silicous rock. The distinguishing feature, which sets perlite apart from other volcanic glasses, is that when heated to a suitable point in its softening range, it expands from four to twenty times its original volume.

WHAT ARE JOHN INNES COMPOSTS?

John Innes Composts are a blend of loam or topsoil, sphagnum moss peat, coarse sand or grit and fertilisers. The loam is screened and sterilised and then mixed with the other ingredients in proportions designed to achieve the optimum air and water-holding capacity and nutrient content for different types and sizes of plants.

Ingredients: Loam, Peat, Fertiliser, Nitrogen, Phosphates, Potash and trace elements