Silica – The Hidden Cost of Chemicals

Discussion in 'Growing Organic Marijuana' started by LumperDawgz2, Jan 16, 2012.

  1. Silica – The Hidden Cost of Chemicals

    A major mineral is missing in many soils and most soil tests do not even monitor its presence. This mineral can increase stress resistance, boost photosynthesis and chlorophyll content, improve drought resistance, salt tolerance and soil fertility and prevent lodging. lt can also reduce insect pressure, frost damage and destructive disease while lowering irrigation rates, neutralising heavy metal toxicity and countering the negative effects of excess sodium. If I were to tell you that this same missing mineral can increase root growth, boost yield and enhance crop quality, you could well ask, “how could we have overlooked something so important?” and you would be correctIt has been a serious oversight. The mineral in question is silicon, and science is rapidly revealing the scope and scale of our silicon neglect.

    Poverty in a Sea of Abundance
    Silicon is not classed as an essential nutrient, but, in response to a wealth of new findings highlighting the importance of this nutrient, that status may soon change. Silicon is the second most abundant mineral on the planet. It is everywhere. Clays are alumina silicates and sand is largely silicon, so how could there be a shortage of silicon? The answer lies in the form of silicon that enters the plant. Plants uptake silicon as silicic acid and this is what is missing in the soil. Something we have done in conventional agriculture appears to have compromised the conversion of insoluble silicon into the plant available form. It may reflect a mineral imbalance or we may have knocked out some of the soil microbe species that solubilise this mineral. It is not yet understood what drove the widespread deficiency but we do know that a healthy, disease suppressive soil should contain 100 ppm of monosilicic acid (as measured in a soil analysis) and very few soils come anywhere near that mark!

    Little was known about the multiple roles of silicon until recently. It was known to be present in every soil but it was only when it became less plant available that it was realised that there may be a link between this loss and a host of growing problems. During the last decade, silicon seems to have become “flavour of the month” in the soil science community. Researchers have delved more deeply and hundreds of papers have been presented at the International Silicon Conferences in Brazil and South Africa. This neglected mineral is now emerging as a key player in proactive pest and disease management and the production of nutrient dense food. If you are not yet aware of the silicon story then this article should serve to fill some gaps.

    Cell Strength is Resilience

    The cell wall in plants is a substantial barrier that must be breached to gain access to the goodies within. A fungal pathogen must drill through this wall with its hyphae to be able to tap into the nutritious cell centre. Once this goal is achieved, the pest has the food source that sponsors its spread, and a disease is born. There is an obvious opportunity here to stop the pathogen in its tracks. What happens if we strengthen that cell wall so that the hyphae buckle? It's simple – the disease cannot gain a foothold and will not spread. Similarly, why would a leaf eating insect choose to wear out his eating gear on silicon-strengthened rock cakes when it can go elsewhere for sponge. Many published papers have now confirmed the exciting potential for increased disease and insect resistance through good silicon nutrition. In one paper presented at the South African conference, soluble silicon used as a soil drench had the equivalent inhibitory effect as phosphorus acid in the management of phytopthora in avocados. However, the silicon-treated plants had much more vigorous roots and canopies. In another case silicon was shown to offer effective management of dreaded black sigatoka in bananas. Other papers reported efficacy against brown rust in sugar cane, powdery mildew in cucurbits, fusarium wilt in potatoes and leaf blast in rice.

    Interestingly, the plant understands the protective potential of silicon, even if we don't. When a disease begins, the plant directs all available silicon to the attack site, to strengthen the surrounding cells and stop or slow the spread of the pathogen. There is a problem here, though, because silicon is immobile once incorporated into the cell wall. It must be in constant supply so that the plant can utilise it at these times. Most soils contain less than half of the soluble silicon required so there can be significant benefits in foliar spraying silicon at the first sign of a disease. This can stop the spread of the disease and many growers are successfully using this strategy.

    cont'd.....
     
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  2. #2 LumperDawgz2, Jan 16, 2012
    Last edited by a moderator: Jan 16, 2012
    Silicon and Sun Power

    Photosynthesis is the most important process on the planet. The green plant is the only source of food and the management of chlorophyll, the green pigment where all the action happens, is the chief role of the farmer. Silicon is a gold sponsor of the sugar factories within the plant as it supports this process in several ways. The leaf is essentially a solar panel, the underside of which also serves to capture the CO2 gas as it rises from the roots and soil life. The better that panel is presented, the more efficient it will prove in capturing sunlight, water and CO2 (the three components of photosynthesis). Silicon strengthens the stem and holds that panel in perfect position. The plant is less likely to droop in warm conditions and more likely to maximise photosynthesis.

    Minerals are the major players in the photosynthesis equation. Blotches, stripes and pale colours, from shortages of minerals, represent the mismanagement of chlorophyll. Sometimes it’s not just the lack of these nutrients but their delivery into the crop that is the issue. Silicon can have a big impact upon mineral uptake. Phloem and xylem are the pathways that govern mineral absorption and the translocation of minerals within the plant. These nutrient highways are built from silicon and their performance will suffer in its absence.

    Calcium is an example of a poorly translocated mineral that will be utilised more efficiently when the nutrient highways are broad and true. Boron is a calcium synergist, which can improve the performance of calcium, but it has recently been recognized that boron also boosts silicon uptake. Boron solubilises insoluble silicon and it is a good idea to combine boron, calcium and silicon in your program to maximise the synergistic potential of the trio. One popular strategy involves the application of boron to the soil in late winter to trigger the release of silicon. The soluble silicon will be used to build the super highways that will improve the sluggish uptake of calcium (needed for cell division during the spring flush).

    Silicon – The Stress Savior

    There are two types of stress that affect production negatively. Abiotic stress involves the negative impact of environmental factors upon living organisms and biotic stress is about pest pressure. Abiotic stress is the single most harmful factor impacting crop growth and productivity on the planet and it can only have more impact as global warming progresses. However, biotic stress is not far behind. Every year since we began the chemical experiment in agriculture there has been an increase in the total amount of chemicals applied on a global scale and every year there has also been a marked increase in pest pressure. The current path is not sustainable; in fact it is not working! There is an obvious relationship between abiotic stress and biotic stress in that environmental factors will increase pest pressure. We are seeing this in all of the countries in which we work. Even in the local ginger industry, right on our doorstep, growers are experiencing pythium pressure unlike anything they have previously experienced. This destructive fungus has found a new niche in the wettest growing season ever. This does not represent a deficiency of fungicides but rather it highlights the desperate need for a more holistic approach that will offer a greater level of inherent protection during times of stress.

    Silicon can reduce the impact of both abiotic and biotic stressors and it represents an essential component of a program designed to create a disease suppressive soil and stress resistant plants. The stronger the cell wall, the more stress resistant the plant, whether that stress is from pathogens or non-living factors.

    Part of the climate change forecast is an increase in extreme weather events. Wind can be particularly destructive in that it can promote lodging, which can render the crop unharvestible. At the most recent silicon conference, Iranian researcher, A. Fallah, presented a paper reporting a reduction of silicon within the plant associated with high nitrogen usage. It is already understood that over application of nitrogen has a nutrient diluting effect and that the mineral most affected is potassium. Now we understand that mismanagement of nitrogen can also impact silicon nutrition and the associated protective effect of this mineral. In this instance, weaker stem strength and increased susceptibility to lodging were noted in the rice crop studied. Fallah reported much stronger stems and resistance to lodging in silicon treated crops.

    One of the stressors that is becoming more of an issue in many soils is the oversupply of heavy metals, salts and some trace minerals. In all cases, silicon has been shown to mitigate the stress. Copper (Cu) can build up in the soil due to the overuse of fungicides. We have found humates a valuable tool to neutralise the negatives associated with this excess. Silica has been effective in mitigating the effect of a variety of heavy metals but recent US research suggests that silicon may be a viable management tool in high copper soils. J. Li, J. Frankz and S. Leisner working in flower crops in Ohio, found that silicon could very effectively mitigate Cu toxicity stress and the improvement was measured on multiple levels.

    Swedish researchers working in cadmium contaminated soils found that the higher the silicon level in the plant, the lower the cadmium level. In fact, there was 60% less cadmium in the silica treated food grains.

    In some exciting Russian research involving wheat, silica was shown to alleviate salt stress quite dramatically. Wheat is notoriously sensitive to high salinity and the salt created a major decrease in photosynthesis. The addition of silicon to the soil resulted in increases in photosynthesis ranging from 158% to 520% depending upon the salt concentration in the soil. This is one of several studies highlighting the silicon link to salt management. We always recommend the inclusion of small amounts of humic acid and potassium silicate with every irrigation, to manage saline irrigation water.

    A South Australian study reported reduced drought stress and an associated reduction in pest pressure following silicon treatment. This study found that applied silicon mitigated the increased insect pressure that was a direct effect of high levels of nitrogen. Not only does high N shut down silica uptake but applied silica can also compensate for this nitrogen mismanagement.

    Cold stress can even be addressed with silicon. South African scientists working with bananas have shown that silicon protected the plants from cold damage and that an associated increase in vigour decreased the banana’s susceptibility to Fusarium Wilt.

    This enhanced protection from disease has been well researched. A recent Japanese study entitled “Silicon in the Control of Diseases in Rice, Sorghum and Soybean”, found reductions in brown spot pressure that varied between 35% and 75% in rice studies. They found significant reductions in anthracnose in silicon-treated sorghum and the results were quite dramatic when foliar applying potassium silicate to manage soybean rust. They concluded their paper with the following words; “The results of these studies underscore the importance of Si to increase plant resistance to foliar disease”.

    This increase in disease resistance was originally thought to be related to the “barrier effect” linked to increased cell strength, but it is now understood to be also related to increased plant immunity.

    cont'd.....
     
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  3. Silicon-Based Immunity

    One of the most dynamic research streams in agricultural science relates to the investigation of plant immunity and the triggers that activates the plant to fight its own battles. It is now understood that the plant has an immune system, which can be both monitored and magnified. Salicylic acid, for example, the biochemical upon which aspirin is based, activates the plant’s immune system. Aloe vera is the richest natural source of this compound and many of our growers benefit from the inclusion of this plant extract in their programs.

    Recently, silicon has been found to trigger the production of a suite of compounds that fuel immunity. This mineral is now seen as an integral tool in proactive pest management as it offers both protective cell strength while also fuelling a robust defense system.

    Phenolic compounds are one of the biochemicals that are part of this defense system and these compounds are now recognised as key players in the protection of avocado trees from Phytopthora cinnamoni. T.F Bekker, et al, from the University of Pretoria, conducted research which demonstrated that soil applications of potassium silicate to soils affected by this disease, increased the total phenolic content of the avocado root tissue.

    It is interesting to note that this silicon-based, immune response is most pronounced when there is existing disease pressure. It’s almost like the plant calls in the heavy artillery when the going gets tough! A Canadian paper presented at the South African conference involved the study of 30,000 genes. The researchers reported that unstressed plants appeared to be minimally affected by silicon feeding with the associated up regulating of only two genes. (Note: upregulation is the process by which a cell increases the quantity of a cellular component such as RNA or protein in response to an external variable.) However, in stressed plants (affected by powdery mildew) there was an up regulation of a number of genes. A Spanish paper also covered the Powdery Mildew control potential of silicon and they found that the inclusion of amino acids with the silicon fertiliser enhanced the response.

    Russian researchers have hypothesised that the plant immune system requires mobile silica compounds and if there is luxury levels of silica available to the plant there will be additional synthesis of stress protection molecules. A co-operative research effort between American and Japanese scientists showed that silica related resistance involves multiple pathways and that silica amendment clearly alters plant defense signaling, increasing the plant’s disease resistance.

    Fertiliser Sources of Silicon

    Silica fertilisers are available in liquid and solid form and the liquids offer the most rapid response. Silicon is found in good levels in rock mineral fertilisers and in rock phosphate and guano products. However, this is not the plant available form of the mineral and, depending on the particle size, it may take many years for the mineral to become available. This is not the case if the fertiliser is a calcium silicate or magnesium silicate but you need to ask about the solubility of any silica fertiliser you may be considering. This is also not the case if these materials are micronised.

    Diatomaceous earth in the amorphous form is a very rich source of insoluble silica. The material is basically the exoskeletons of tiny prehistoric creatures called diatoms. These remains contain up to 85% silica dioxide and the silica shell is sharp and jagged under a microscope, almost like a broken razor blade. Diatomaceous earth has been used as a natural insecticide for decades, as the jagged, little razor blades can cut up the offending insect’s exoskeleton causing the creature to dehydrate and die. This material is also used internally as a natural means to control intestinal parasites. The rich silica lode fromdiatomaceous earth can be made plant-available by micronising the material right down to a tiny particle size of 5 microns. It can then be held in a liquid suspension and applied via boom spray or fertigation. As little as 5 litres of liquid, micronized diatomaceous earth per hectare, applied through fertigation on a regular basis, can lift leaf levels of silica into the luxury zone, with all of the associated benefits.

    Potassium silicate is a good soluble form of silica but it is not compatible with many other fertilisers and must often be applied as a standalone. One way out of this limitation is to use a pre-formulated potassium silicate-based fertiliser which includes other synergists.

    Note: Potassium Silicate = Dyna-Grow Pro-TeKt

    More at original link.........
     
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  4. #4 jerry111165, Jan 16, 2012
    Last edited by a moderator: Jan 16, 2012
    DE mixed into a soil mix will take care of this then - in what approximate amounts?

    Jerry.

    Ps - I would also imagine that the cheapo pool grade would be just fine?
     
  5. Good stuff! Thanks LD.

    I alternate ~1/2tsp and ~1/4tsp with my waterings all the time with great results. I also attribute the regular use of silicon with finally eliminating my long standing fungus gnat problem.
     
  6. #6 WeeDroid, Jan 16, 2012
    Last edited by a moderator: Jan 16, 2012
    nice one LD, thank you. :)

    I find it most interesting that guanos are considered a source. Maybe more than just tomato farmers will be going after the bat guanos now. ;)
     
  7. I'm diggin the Pro-Tekt. Thanks for the added info LD.

    I can say with a fair amount of confidence that, the addition of Pro-Tekt this round has given me noticeably thicker secondary branching. And that alone is worth it.
    Silica in some form will stay in my garden. I recommend it to every grower I know.


    BeZ...V
     
  8. [quote name='"WeeDroid"']nice one LD, thank you. :)

    I find it most interesting that guanos are considered a source. Maybe more than just tomato farmers will be going after the bat guanos now. ;)[/quote]

    Yeah you may be on to something composting the bat guanos you already have WeeDroid. Even if it takes some amount of time for the Silica to be available, my current soil with guano added will be used over and over again in some form.


    BeZ...V
     
  9. Well, at this point I'm just phasing out my bat guanos, but I may reexamine that issue in light of this article. I would still be using composted chicken guano in any case.

    I would think that my silicon levels are okay, since I add things like crab meal, neem, fish bone meal, etc., and don't use chemical feeds.

    I'll still be getting the Pro-Tekt when I start my next crop though.
     
  10. It's worth mentioning that liquid silica will raise waters ph. DE will raise soil ph. Just so you know.....MIW
     
  11. Good call MIW.
     

  12. I use the ProTekt, but am going to start adding the DE to the mix for a long term supply/source. ~1cup/cf seems to be a common starting point.

    It is slow, and I sorta figure to treat it like greensand and not expect much of anything till the second or third year.

    I would also expect the pool grade would be fine for a soil mix.

    Suggest you still snag some ProTekt though for more immediate results. It's cheap, ~$12/qt, and using 1/4 to 1/2 tsp/gallon, that qt lasts a loooong time.

    Wet
     
  13. #13 LumperDawgz2, Jan 16, 2012
    Last edited by a moderator: Jan 16, 2012
    Dyna-Gro Pro-TeKt is easily sourced and is usually carries a fair price at mainstream nurseries.

    Here's the information from the their label of this product:

    Potassium (K2O) 3.7%
    Silicon (SiO2) 7.8%%

    The 'good dude' price is around $32.00 per gallon around here.

    As usual, many of the products promoted by grow stores as a Silica source are either watered down or include Sodium Silicate (Botanicare Silica Blast for example).

    And then there's Advanced Nutrients' Rhino Skin with prices that are the usual stupidity.

    Web sites like Hydro-Gardens carry the base materials used in hydroponics like Calcium Chloride, Di-Ammonium Phosphate, Potassium Chloride, etc.

    This one also carries Potassium Silicate and here are the numbers from their label:

    Silicon (SiO2) - 26.5%

    Their price is $18.95 per gallon plus S&H (and their charges are fair).

    According to them, 3 oz. per 100 gallons will give you 100 ppm which means absolutely nothing to me but others who understand these ratios can jump in and help out.

    Pretty inexpensive - I would think that a gallon of this concentrate would last 4 or 5 years for most medical gardeners.

    HTH

    LD
     
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  14. #14 Chunk, Jan 16, 2012
    Last edited by a moderator: Jan 22, 2012

    Or......you can collect some Horsetail Fern "Equisetum arvense" and make a silica/silicon rich FPE and enjoy the other elements and compounds it provides.:)

    chunk
     
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  15. Yes indeed - Horsetail Ferns contains Silica at 60,000 - 97,000 ppm

    Here's a few other benefits from this plant material:

    Silicic Acid - 80,000 ppm (rooting agent)
    Phosphorus - 14,762 ppm (Dank Dumb agent!)
    Calcium - 24,000 (prevents Cal-Mag Lockout!)
    Magnesium - 4,730 PPM

    NOTE: Note the ratio of Calcium:Magnesium in this and most other plant materials.

    Heh......

    But the biggest benefit are Carbohydrates - 737,000 ppm

    I'll let Chunk explain the role of Carbohydrates in soil biology from the information he's been gathering in the past couple of weeks.

    Once again, free wins out over bottled solutions.

    LD
     
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  16. Probing The Mechanisms Of Silicon-Mediated Pathogen Resistance

    Key Laboratory of Ecological Agriculture of Ministry of Agriculture
    South China Agricultural University
    Guangzhou China

    2College of Resources and Environmental Science
    China Agricultural University
    Beijing China

    Abstract

    Silicon is the second most abundant mineral element in soil, it has important role in alleviating various environmental stresses and enhancing plant resistance against pathogen, but the exact mechanism by which Si mediates pathogen resistance remains unclear. One of the resistance mechanisms is related to silicon deposition in leaf that acts as a physical barrier to hinder pathogen penetration. But more evidence show that silicon can induce defense responses that are functionally similar to systemic acquired resistance, Si-treated plants can significantly increase antioxidant enzyme activities and the production of antifungal compounds such as phenolic metabolism product, phytoalexins and pathogenesis-related proteins etc. Molecular and biochemical detections show that Si can activate the expression of defense-related genes and may play important role in the transduction of plant stress signal such as salicylic acid, jasmonic acid and ethylene.

    Introduction

    Although silicon (Si) has not been considered as an essential element for plant nutrition, the beneficial effects of this element on growth and development of many plant species have been demonstrated. Furthermore, the beneficial role of silicon in enhancing plant resistance to various biotic and abiotic stresses is particularly evident. Numerous evidence showed that Si could control plant disease caused by fungi and bacteria, such as blast and sheath blight in rice, powdery mildew in wheat, barley, cucumber and Arabiopsis, ring spot in sugarcane,8 rust in cowpea (Vigna unguiculata)5 etc. And the enhanced resistance is associated with the higher deposit of silicon in leaf so as to form physical barrier to impede pathogen penetration and the activation of host defense response.

    But the exact nature of protective effects by silicon in plants, are uncertain and presently the subject of debate. The objective of this review is to discuss the possible mechanisms for Si-enhanced resistance to disease, and the recommended further studies are also proposed.

    Physical Barrier Mechanism

    Since Si was found to control plant disease, physical barrier was traditionally used to explain its role in enhancing pathogen resistance. Si can accumulate and deposit beneath the cuticle to form a cuticle-Si double layer and thereby interfere with pathogen's penetration through mechanical barrier. A blast-resistant rice cultivar has more silicified cells than a susceptible cultivar.

    Si manifested its effect to establish blockage to ingress by fungus.15 Kim et al.,2 reported that silicified epidermal cell walls were closely associated with the reduced blast severity in susceptible and partially resistant cultivars. The prevalence of papillae in Si treatment could increase pathogen resistance against B. graminis f.sp. tritici.

    Cytological evidence showed that Si-induced resistance to M. grisea in rice was correlated with a specific leaf cell reaction that interferes with the development of M. grisea. Liang et al., reported that foliar applied Si only produced physical barrier and osmotic effect, but root applied Si leaded to systemic acquired resistance when Cucumis sativus. plants were infected by powdery mildew pathogen. Studies by Zhang et al., demonstrated that Si-treated rice plants infected by sheath blight pathogen Rhizoctonia solani had much more silica cells and papillae. Based on light microscopic observation of the adaxial surface of rice leaves amended with or without Si, Hayasaka et al., further confirmed that Si in the leaf epidermis may confer resistance against appressorial penetration. Our previous study showed that Si treatment and M. grisea inoculation resulted in higher Si deposit in rice leaves from the zones where fungus grew for both susceptible and resistant near-isogenic lines, and the size of silica cells was larger than that in no Si-treated plants.

    Biochemical Mechanism

    Although early and recent studies partly support the hypothesis of cell silicifiation, silicon deposit and papilla formation to explain enhanced resistance of plants against pathogen, this mechanism has been always strongly doubted. It was demonstrated that insoluble Si could accumulate and polymerize at fungal penetration sites or in epidermal cell walls, but not associated with the increased resistance. Prophylactic effect against powdery mildew was lost when Si feeding to cucumber plants was interrupted.9 Heine et al., reported that the accumulation of Si in root cell walls did not represent a physical barrier to the spread of Pythium aphanidermatum in roots of bitter gourd and tomato.

    When infected with necrotizing pathogens, many plants develop an enhanced resistance to against further pathogen attack, which is referred to as systemic acquired resistance (SAR). Silicon could induce defense responses similar to SAR. Several studies showed that lower disease severity in the Si-treated plants was in line with higher activity of protective enzymes (POD, PPO and PAL) in leaves of rice, wheat and cucumber.

    And these enzymes had important role in regulating the production of accumulation of antifungal compounds such as phenolic metabolism product (lignin), phytoalexins and pathogenesis-related proteins in plants. Si application can induce the production the antifungal compounds after the penetration of pathogens enter the epidermal cell.

    It was demonstrated that Si treatment resulted in the increase of flavonoid phytoalexin in cucumber plants infected by powdery mildew (Podosphaera xanthii). Another study reported that Si-induced resistance to blast (M. grisea) in rice was related to the production of phytoalexin(s), which were mainly momilactones A and B. Si can increase the production lignin-carbohydrate complexes in the cell wall of rice epidermal cells. Our studies showed that Si-treated infected plants significantly increased lignin content of susceptible rice line compared with no Si-treated plants.

    Ample evidence showed that Si alone has apparently no effect on the metabolism of plants growing in a controlled unstressed environment, but it will alleviate the stress (including abiotic and biotic stress) and modulates the stress response in plants, and this role is active.

    Molecular Mechanism

    However, silicon mediated pathogen resistance is a complex phenomena that is worthy of more detailed analysis at the molecular and biochemical level. It was reported that gene expression had no significant difference between Si-treated and non-treated plants in the absence of stress. A study by Kauss et al., showed that during the induction of Systemic Acquired Resistance (SAR) mediated by silicon in cucumber, the express of a gene encoding a novel proline-rich protein was enhanced, this protein was associated to cell wall reinforcement at the site of the attempted penetration of fungi into epidermal cells.

    By using molecular biology techniques such as subtractive cDNA libraries or microarrays, Fauteux et al., assessed the defense-related genes expressed in control or infected Arabidopsis plants, their microarray results show that Si-treated plants react to pathogen inoculation through the upregulation of defense- and pathogenesis-related genes, which confirms that silicon plays an active role in enhancing host resistance to pathogen infection.
     
  17. So could i add playsand/silica sand to my soil to help with this? because I already have and put sand in my soil mixes usually.
     
  18. Jimmy Carter

    It comes down to availability. Plant materials are your best source - besides Horsetail Ferns you could consider using Comfrey, Stinging Nettles, Dandelions and Yarrow flowers.

    Most of these plant materials can be sourced as a dried product but the best way is to simply buy the seeds from Horizon Herbs and grow them yourself.

    Chump-change.

    LD
     
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  19. [quote name='"jerry111165"']DE mixed into a soil mix will take care of this then - in what approximate amounts?

    Jerry.

    Ps - I would also imagine that the cheapo pool grade would be just fine?[/quote]

    Jerry- IIRC when I was doing some research on silica influence on brix levels. Pool silica was a no no.

    LD - just found some locally sourced basalt rock dust that is going to replace my glacial rock dust for this very reason. Not to mention cheaper than GRD for me.
     
  20. Cheaper is always better when it comes to rock dusts, IMHO!

    We're finally going to have basalt rock dust available in a couple of months at the local organic farm store.

    I've been invited to prepare some class materials on mineralization for this store and I wanted in include Basalt. This store has garden classes in the spring on Saturday morning.

    Hey - I get a free bag of kelp meal for my efforts! LMAO

    LD
     
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