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Agricultural Grade

Agricultural Grade

Silica has proven to be essential for crop production. Diminishing soil silica levels are believed to be responsible for the reduction in crop yield in all developed countries around the world.


Research has identified Silica is an essential soil additive and vital if we hope to improve crop production and bring crop yields back to what we want them to be.


Understanding the process of Nutrient Depletion


Nutrients leave the soil in two main ways


One is via the plant, the plant takes up the nutrient from the soil and is harvested, and when the plant is harvested the nutrient is also harvested. As the silica that was once available and present in the soil is now contained within the plant we can understand why adding Silica is so important. (This process is the same for other nutrients).


The other is via leaching, which occurs when rain or irrigation water dissolves the nutrient and the water runs off the soils.


This means that every time we harvest our crops we remove more of the essential nutrients our plants require to remain healthy. The problem with Silica is that it has never been replaced because it was thought to be in abundant supplies. And because Silica deficiency is not obvious as say nitrogen deficiency we have continued to ignore this vital element.


Why has Silica not been identified earlier?


As Silica is an abundant mineral and found in all soils and plants early scientists believed that like oxygen it would remain present – always. But the truth is that Silica has been depleted just like all other minerals, while the symptoms were evident the cause was difficult to identify.


However, Russia and Japan have been using Silica for many years with Japanese rice farmers considering it an essential nutrient. Sugar farmers in Florida began using Silica fertilizer in 1994 and noticed immediate benefits (within the first year). Australian farmers are slowly adopting to using Silica as part of regular farming practice and are too noticing immediate benefits.


Below are articles from the North Queensland Register of trials carried out on Sugar Cane in the Hinchinbrook and Burdekin area of Queensland.


Silica the secret for Hinchinbrook cane 02 Oct, 2009 08:14 AM North Queensland Register Source: http://www.northqueenslandreg 


With around 55,000 hectares of cane being grown in the Herbert River region each year, it is the most important primary industry in the Hinchinbrook Shire. But as everyone who grows cane knows, the price they get for their sugar varies markedly, and continuing to increase productivity while reducing input costs is the key to sustainability. This is why Herbert River director of the Australian Cane Farmers Association Carol Mackee and her husband Lex ran a small trial last year using silica on their cane in the hope of improving its yield. Silica is a nutrient needed by plants just as much as nitrogen, phosphorus or potash - a fact Carol discovered while developing a submission to the Federal Government's inquiry into fertiliser pricing. She also found the BSES had identified it as a limiting element in some high-rainfall areas of the wet tropics. Then she discovered Si-Soil Technologies had a diatomaceous earth mine in FNQ that contains high levels of plant-available silica and the company was interested in trialling it on sugarcane, so they decided to give it a go. They bought 24 tonnes and in September 2008 spread it with a Vicon fertiliser spreader on the poor sandy grey loam soils at their Long Pocket farm. It was applied over plant cane and a block of ratoons at 1t/ha. One plant cane block of NQ239 was used as a trial with silica only applied to 1ha. The diatomaceous earth was spread over the emerging cane and in the ratoon block over the trash blanket. The blocks had already received their fertiliser, but because in 2008 urea had doubled in price, the amount of N used was reduced by 40 percent. The first thing that became obvious in the blocks that had received silica was the colour of the cane, which changed to a deep green. In the trial block of plant cane, it outgrew the rows next to it very quickly, ending up 600mm taller, and that height difference lasted right through to harvest. There were also no weeds in the silica trial rows, put down to the canopy shading the ground much ealier than the untreated plant cane. Army worm was a problem when the cane was fertilised with the silica, but within three weeks of applying it, the treated blocks were free of the pest. The other noticeable difference in the treated cane was it took three weeks longer to show signs of wilting in dry spells compared to the untreated cane. At harvest, the hectare of treated plant cane yielded 71t, while the rest of the block averaged 41t/ha - the low yield put down to the adverse effects of the floods earlier in the year. As NQ239 is a newly released smut-resistant variety, it was all used as plant cane, so no CCS figures are available; however, the ratoon block averaged half a unit better than the cane around it. Lex said the improved yield of the plant cane more than paid the $320 + freight cost of the silica, so this year they have expanded their trial by applying it to half of each block of plant cane. They are now awaiting the soil test results from the blocks that had silica applied last year to find out from Si-Soil Technologies' Dr Vladimir Matichenkov whether it will be necessary to apply it each year, as in some soils it isn't.



Silica one key to improved cane results 21 Sep, 2010 02:41 PM


A couple of years ago Australian Sustainable Agriculture, which has a silica mine near Mount Garnet, began spreading the word that our tropical high-rainfall soils are generally deficient in plant-available silica. It was news to most of us, as was the claim by the company that silica is equally as necessary for plant growth as N, P or K, and it is the weak link in the chain, as no matter how much NPK is applied, the plant can't benefit from it if silica is lacking. That information resulted in some cane farmers in the Herbert River District trialling it on the 2008-09 crop, which interested 20,000-tonne Burdekin Delta grower Jim Jones, as soil tests from his farm showed his soils were plant-available silica deficient, so he went up to see how the trials in the Herbert were going. "Visually, I could see the cane with added silica was taller, the stools were bigger and the cane was thicker, which convinced me to try some for myself," he told the North Queensland Register. So last year Mr Jones began a trial over five blocks, which involved both ratoon and plant cane and different soil types. Using a fertiliser spreader, he applied 1t of Synergy silica across a portion of each block in areas ranging from 1-10 hectares. It was spread when the cane was half a metre tall, on blocks where the drill lengths were all the same length. The silica was in addition to the normal fertiliser applications. The cost of the silica, including GST and freight was around $410/t, so at the expected 2010 sugar price of $475/t, which makes cane with a 16ccs worth about $50/t, it would require an extra 12t/cane/ha to cover the cost of the purchase and spreading of the silica. Mr Jones said the cane with silica was visually better during the growing period - it was taller and looked thicker and that was evident to anyone who looked at the blocks. At the time of going to press, he had harvested three of the five trial sites and his harvester operator said he could tell when the machine reached a silica drill, as the oil pressure on the chopper blades went up considerably. Although Mr Jones didn't weigh the cane, the rule of thumb he used was the number of 6t bins the drills produced, and the rows with silica cut between 25 percent and 50pc more cane. It also had a higher ccs: the controls averaging CCS 16.2 and the silica drills CCS 16.5. Considering the average production across the Burdekin ranges from 110-125t/cane/ha, the 25pc-50pc increase achieved by Mr Jones would be very profitable, and after seeing the results, he said he'd like to spread it over all his deficient soils, but he has two concerns. The first is the upfront cost of the initial purchase, as it takes 2.5 years from the time the money is outlaid until the final cane payment is received; and he also wants to know whether the silica will need to be applied each year. And that's a question that won't be answered until new soil tests have been taken.


Further references of trials carried out using Australian Sustainable Agriculture DE. Many of these trials have been carried out by Russian Scientist Dr Vladimir Matichenkov. Dr Matichenkov is a world renowned scientist in Silica studies. advantages of Applying Silicon ica - Natural Silicon fertiliser in Queensland – Silicon in banana plants: distribution and interaction with the disease fusarium wilt


The beneficial effects of Silica application has shown to have a direct effect on crop productivity, improving soil fertility, increasing plant health and reducing water requirements resulting in improved resistance to disease, insect attack and drought. In addition to this Silica application will assist plant absorption of other applied fertilizers and soil nutrients resulting in reduced application of fertilizers (such as Phosphors) and chemicals.


Silica has a high content of plant available Silica and a range of desirable trace elements (see analysis) – overall you can expect noticeable improvement in plant health, increased farm income and a reduction in spending on crop inputs.


Adding Silica will

  • Increase crop productivity

  • Improve soil fertility

  • Increase plant health

  • Reduce water requirements

  • Enhance other applied fertilizers efficiency


Resulting in

  • Stronger plant cells and structure

  • Improved resistance to disease and fungi

  • Improved resistance to insect attack

  • Increased drought tolerance and reduce irrigation requirements

  • Increased salt tolerance

  • Reduced chemical and fertilizer costs

  • Increased farm income


Silica can be applied just like any other soil conditioner using standard application equipment. Apply Silica as a side dressing, broadcast, during planting or whatever method suits your farming method.


Silica is used in many industries including farming, landscape gardening, home gardening, golf courses, sports fields and many more.


Application Rates


 1 Tonne (1000kg) per hectare per year


*High quality silica has a residual effect when used in soil and depending on the soil condition prior to first application its subsequent application rate will most likely be reduced.




  • Sprinkle liberally on the ground around trees.

  • Before planting – use 2-5kgs per 15 metre row

  • Mixing with soil – 250g to a 300mm x 300mm hole

  • 500g per 8 lts of water to spray top and underside of leaves

  • Approximate coverage for gardens

  • 250g will treat 25 square metres

  • Sprinkle over plants and vegetables for the control of common pests in the garden. This should be performed regularly as the water will wash off the plants. The wash off will assist with strengthening of plant roots and make the natural minerals in the soil plant available.


 The best rate will depend on the following factors:


  1. Soil properties

  2. Climatic condition

  3. Crop rotation


To assess the need for Si fertilization a number of steps must be considered:


  1. Soil classification and the deficiency of actual, potential and active Si should be developed;

  2. Mapmaking for various regions


We suggest the following grades for soil Si deficiency

Soil deficiency classification


Not deficient soil – Si fertilization or Si-rich soil amendments are not required. Sometimes the application of Si-rich soil amendments would have beneficial effect via acting Si compounds on soil properties and NPK behaviour in the soil-plant system.

Low deficient soil – Si fertilization is necessary for Si-accumulating plants (cereals, grasses). Si-rich soil amendments are required for optimizing P plant nutrition.

Deficient soil - Si fertilizers and Si-rich soil amendments have stable and significant effect on all crops and increase soil fertility. A standard rate of Si application is necessary.

Critically deficient soil – The lack of active Si has a negative effect on crop productivity and environment. High rates of Si fertilizers or Si soil amendments are necessary.


Matichenkov, 2002


CAUTION: Do not confuse natural silica or food-grade Diatomaceous Earth with crystalline silica which is commercially produced by exposing amorphous silica to extreme heat for use in swimming pool filtration systems. Crystalline silica is extremely dangerous and must not be consumed by humans or animals, or used on gardens or agricultural crops.

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