Silicate as a fertiliser

Roots exude acids and bases, oxidizers and reductors, as do most biological soil thingies like bacteria and fungi.

If it wouldn't be bio-available, it wouldn't be present already in a whole lot of plant cells.

Rare is a very elastic phrasing in molecular science. As in: what sounds rare to us, might not be very "rare" in the actual world when expressed in numbers.
With a rough estimation there are 10000000000000000000000 (1x1^22)molecules of silicon dioxide in a grain of sand. Let's say a grain of sand is only 1% SiO2 and just 1% of that SiO2 becomes bioavailable.
That's a whopping 1000000000000000000 available molecules, eighteen zeroes.
Let's say it's even less rare, let's make it one millionth of a percent. That's still 10000000000 available molecules per grain of sand. Is that ten trillion?
This loops us back to the actual science at hand, because there is a mention of increased resistance-related gene expression. An increase can be measured when the expression exceeds 1x the "normal" expression level. Depending on the definition of normal (are we using a silica devoid control, or something else?), the applied statistics and the sequencing depth, one can detect up to a millionth of an increase and call it significant if we fiddle with what's normal and how we statistically approach it.

Maybe one should look up the composition and bioavailability from our own media like akadama, lava rock, granite, DE..

What I'm saying is that I believe the science behind it, just not the marketing.
The poster of the study, which the guy is co-author of, can be viewed here: https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1008&context=cpl_hydroponics
To me, it shows that the wollastonite is an easy releaser but it stops working just about when rice hulls are picking up the speed. If the soil pH ends up outside the "perfect range -2 or +2 pH points", which for the wollastonite seems to be within.. a week?
Then I'm not sure what to make of this.
If the release over the course of 120 days, which is about my growing season, drops back to regular levels and screws up the pH within days.. Man, I don't know.
Those Rsquared values seem to tell that the data is all over the place and release is anything but linear.


It seems that all positive effects of external application are diminished when plants are already grown in silicium rich media.. Which is basically every bonsai medium out there.

It sounds off to me that stuff like rockwool and perlite (40-80% SiO2) give off so little of it.

Summarized I think that it can be a great addition, but laying too much focus on it as a ferilizer can be dangerous because it can and will fiddle with the pH. If you're using tap water, the soil can become alkaline into the caustic to human skin levels.
The pH effect definitely could be a concern so maybe don’t use it on Azalea and other species loving acidic soil. I was already thinking to not use more than a few applications each season and only when knowing you water pH.

Rockwool releasing very little is in line what I remember that the silica research started in rockwool and hydroponics (obvi on the last one).

In general your view confirmed my ideas so thanks for sharing.
 
Read my previous contributions no all silica is easily available for uptake in plants.
Re-read what Guy Wires Guy wrote about the ability of plants to break down minerals in soils
Silica is a very common component of most soils. Hell even rain and other weathering effects will make it bioavailable in the more than enough amounts that plants can use and will not be a limiting factor.

Not buying that silica is used by plants in such huge amounts that we need to add it in comparatively huge amounts to what they really need.
 
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Re-read what Guy Wires Guy wrote about the ability of plants to break down minerals in soils
Silica is a very common component of most soils. Hell even rain and other weathering effects will make it bioavailable in the more than enough amounts that plants can use and will not be a limiting factor.

Not buying that silica is used by plants in such huge amounts that we need to add it in comparatively huge amounts to what they really need.
I did but neither of us know how much becomes available from breakdown.

There is enough evidence available that silicate is beneficial to plants and the availability varies per substate and environment. There is no specific information available on bonsai soils so I would not assume it is not a limiting factor. He also wrote.
It sounds off to me that stuff like rockwool and perlite (40-80% SiO2) give off so little of it.

Summarized I think that it can be a great addition, but laying too much focus on it as a ferilizer can be dangerous because it can and will fiddle with the pH. If you're using tap water, the soil can become alkaline into the caustic to human skin levels.
The part on availability from rockwool and perlite both high in SiO2 confirms my view and might be reality.
 
I did but neither of us know how much becomes available from breakdown.

There is enough evidence available that silicate is beneficial to plants and the availability varies per substate and environment. There is no specific information available on bonsai soils so I would not assume it is not a limiting factor. He also wrote.

The part on availability from rockwool and perlite both high in SiO2 confirms my view and might be reality.

The composition of both lava and pumice are widely known. Both have Silica in them. Both will leech/break down somewhat. In addition, micro nutrients/minerals are included in many fertilizers.

Yes he also wrote "but laying too much focus on it as a ferilizer can be dangerous because it can and will fiddle with the pH. If you're using tap water, the soil can become alkaline into the caustic to human skin levels."

Many plants do not like high pH soils, including azalea, pine, maple.

You can believe what you like and pour whatever snake oil the salesman wants to sell you on your trees if you want. I believe it's not necessary and risky to use something that as stated can raise the soil pH to dangerous levels.

Neither of us is going to convince each other otherwise so before this turns into the new soil wars, let's just agree to disagree and move on..
 
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Depends on where the beach is. Beaches near large coral reefs have high amounts of calcium. Beaches here in NY and along the east coast are silicate sands.
I’ll have to find out if the beaches of the Great Lakes are silicate sands. The ocean sands may be quite different than inland lakes.
 
I’ll have to find out if the beaches of the Great Lakes are silicate sands. The ocean sands may be quite different than inland lakes.
Most likely silicate, the non silicate beaches are associated with coral reefs (parrot fish poop).
 
Neither of us is going to convince each other otherwise so before this turns into the new soil wars, let's just agree to disagree and move on..
Fine for me but it is not about opinions and Wollastonite is cheap.

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Silicates are generally inert chemically. Hence they are common minerals. Their resiliency also recommends their use as building materials.

When treated with calcium oxides and water, silicate minerals form Portland cement.

Equilibria involving hydrolysis of silicate minerals are difficult to study. The chief challenge is the very low solubility of SiO44-and its various protonated forms. Such equilibria are relevant to the processes occurring on geological time scales.[2][3] Some plants excrete ligands that dissolve silicates, a step in biomineralization.

So the main question here is to what extend do our bonsai excrete ligands to make silicates bio available.
 
Fine for me but it is not about opinions and Wollastonite is cheap.

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So the main question here is to what extend do our bonsai excrete ligands to make silicates bio available.
If it is truly chemically inert then it will not be bioavailable to trees no matter what you do.

That isn't the case though because diatoms use it to make cell walls by extracting it from water. It is also found in plant tissues but in high quantities in some species (research states mostly in grasses, fiber crops ie rice, wheat, hemp). These plants accumulate Silica while other plants (ie tomato) exclude it. Other plants are neutral to it. The accumulators show some benefits but researchers note plants develop well without it.

Lastly being that it is the second most common element found in the earth's crust, which lava and pumice literally comes out as molten crust. The paragraphs above the one you quoted about silicates being generally inert also state that there are different forms of silicates and some are water soluble. The most dominant form of silica in soils is silicic acid which is bioavailable.

Other studies show there is evidence of mycorrhizal weathering (besides weathering from winds and water, etc) of silicate containing particles in soil. However, low levels of silcates were found in tree tissues of coniferous trees found in a high silicate temperate environment except near the base of the tree where the Silica was introduced via contamination (deposition on the bark) rather than root uptake. Trees in warmer climates had more silica in their tissues. There is some relationship with temperature and loss with freezing. There also seems to be a relationship with pH (more acidic) that will make it more available. There is also another relationship between higher CO2 in the atmosphere and passive Silica uptake due to production driven by the higher CO2. But that higher CO2 caused other detrimental effects in the elemental and nutrient composition of the leaves.

In short, it's very species specific whether the plant accumulates, excludes or is neutral to Silica in soils. Our trees may not produce ligands necessary to uptake Silica because they just dont need to or other processes in their environment allows uptake through water.

It's super abundant in soils, including our bonsai soils as well as included in any good quality fertilizer.

My own review of the scientific literature, not a product website, leads me to conclude that it is not necessary to add it as an additional supplement. It is already available as a trace element in common fertilizers in a form that can be taken up by the plant in the quantities they need.
 
If it is truly chemically inert then it will not be bioavailable to trees no matter what you do.

That isn't the case though because diatoms use it to make cell walls by extracting it from water. It is also found in plant tissues but in high quantities in some species (research states mostly in grasses, fiber crops ie rice, wheat, hemp). These plants accumulate Silica while other plants (ie tomato) exclude it. Other plants are neutral to it. The accumulators show some benefits but researchers note plants develop well without it.

Lastly being that it is the second most common element found in the earth's crust, which lava and pumice literally comes out as molten crust. The paragraphs above the one you quoted about silicates being generally inert also state that there are different forms of silicates and some are water soluble. The most dominant form of silica in soils is silicic acid which is bioavailable.

Other studies show there is evidence of mycorrhizal weathering (besides weathering from winds and water, etc) of silicate containing particles in soil. However, low levels of silcates were found in tree tissues of coniferous trees found in a high silicate temperate environment except near the base of the tree where the Silica was introduced via contamination (deposition on the bark) rather than root uptake. Trees in warmer climates had more silica in their tissues. There is some relationship with temperature and loss with freezing. There also seems to be a relationship with pH (more acidic) that will make it more available. There is also another relationship between higher CO2 in the atmosphere and passive Silica uptake due to production driven by the higher CO2. But that higher CO2 caused other detrimental effects in the elemental and nutrient composition of the leaves.

In short, it's very species specific whether the plant accumulates, excludes or is neutral to Silica in soils. Our trees may not produce ligands necessary to uptake Silica because they just dont need to or other processes in their environment allows uptake through water.

It's super abundant in soils, including our bonsai soils as well as included in any good quality fertilizer.

My own review of the scientific literature, not a product website, leads me to conclude that it is not necessary to add it as an additional supplement. It is already available as a trace element in common fertilizers in a form that can be taken up by the plant in the quantities they need.
Thanks good contribution.
 
:: Puts on experienced geologist hat ::

I am extremely skeptical of this whole thing.

Everyone talking about sand is correct, this would be a bad source of "silicates" because it doesn't weather noticeably. But this is also the core of the issue. Sand is essentially "pure silicate", and the fact it doesn't break down is a clue to the fact that "silicate" is inherently not particularly water-soluble.

However the blurb on the product we're talking about says it is "calcium silicate (CaSiO3)", not quartz sand. CaSiO3 is plagioclase feldspar, an extremely common rock-forming mineral, and particularly abundant in igneous rocks like "lava rock" (whatever it actually is), pumice, and granite. I guess if it were powdered, that might make it add its breakdown products to soil faster, but it's not actually different from what is already in the soils.

Moreover, plagioclase breaks down to form clay minerals. There is no magical release of "silicates" as a bioavailable thing into the soil, just more clays. And we already have plenty of clay minerals knocking about in our soils - this is basically what acadama is, as well as, e.g., moler.

There might be benefits to putting this stuff into some more exotic soils, e.g., bark only, 100% perlite, very free-draining stuff. But I don't believe you'll achieve anything that throwing a bit of acadama in there would not.
 
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I've tried Silica supplementation, using hydroponic supplements which claim high availability. I would reiterate the PH thing, you will absolutely need a calibrated digital PH meter and PH down to compensate quite a lot to achieve normal rainwater levels of acidity.


Can't say I noticed much difference to my trees. Makes a lot more sense for grasses.
 
:: Puts on experienced geologist hat ::

I am extremely skeptical of this whole thing.

Everyone talking about sand is correct, this would be a bad source of "silicates" because it doesn't weather noticeably. But this is also the core of the issue. Sand is essentially "pure silicate", and the fact it doesn't break down is a clue to the fact that "silicate" is inherently not particularly water-soluble.

However the blurb on the product we're talking about says it is "calcium silicate (CaSiO3)", not quartz sand. CaSiO3 is plagioclase feldspar, an extremely common rock-forming mineral, and particularly abundant in igneous rocks like "lava rock" (whatever it actually is), pumice, and granite. I guess if it were powdered, that might make it add its breakdown products to soil faster, but it's not actually different from what is already in the soils.

Moreover, plagioclase breaks down to form clay minerals. There is no magical release of "silicates" as a bioavailable thing into the soil, just more clays. And we already have plenty of clay minerals knocking about in our soils - this is basically what acadama is, as well as, e.g., moler.

There might be benefits to putting this stuff into some more exotic soils, e.g., bark only, 100% perlite, very free-draining stuff. But I don't believe you'll achieve anything that throwing a bit of acadama in there would not.
I guess that means I will start pottery and use the Wollastonite for dulling glazes.

Thanks a lot that was exactly the information that was missing. Will still try it on my trees in development that in organic mixes.
 
I don't know if this is relevant for this post but I saw Asao koide's using "Potato Silica" as a root promoter in his Sekka Hinoki cuttings. He must know something we don't know ;).


This is the product https://www.amazon.co.jp/-/en/potato-silica-500g/dp/B01AFVHHGI
SiO2 73% among other minerals.
Yes, i was curious about silicate powder too, as not only this japanese chap is using this as a soil additive. Some other growers in Japan are using it too.
But as whether its beneficial to all species, the jury is still out.

I just purchase some silicate powder online and will try it out this season and let this thread know the findings.

The description and instructions of what I bought is written below as such:


Natural Silicate powder​

Silicate is an essential element for higher plants, especially when growing with water as a substrate. New pH neutral Silicate contains ancient deposits of biologically transformed organic matter, plus naturally formed silicic acid clay.

Terra Aquatica Silicate provides a naturally soluble form of silicon which enters plant cells and builds a hardened shield against disease and insect attack.

Silicate’s natural colloids improve cation exchange capacity to nutrient solutions improving nutrient availability to your plants.

Silicate stabilises nutrient solution pH and conductivity which reduces stress for rapidly growing plants.

Terra Aquatica Silicate also protects against toxicity from metals.

Last but not least, Silicate contains more than 60 minerals, which add more nutritive elements for plants to thrive on.

Our new Silicate comes from ancient deposits and is very similar to the old one, however, it has a few advantages:
  • It is richer in silicate
  • Its particles size is smaller, for a better solubility of the silicate
  • It incorporates more carbonates for a better pH stability.
  • It offers calcium to the plant.
How to use:
  • At the base of each plant : sprinkle 1 teaspoon (about 4g).
  • In nutrient solution : 4g/10L
  • Powder directly on the leaves: 10 g to 50g/m2 or by foliar spraying of a solution of 4g for 10L of water.
Use with: IMPORTANT NOTICE: SILICATE AND BENEFICIAL MICROORGANISMS:

Silicate works in synergy with all our products. However alongside beneficial micro-organisms (Trikologic, Trikologic S) use only in foliar application, or localized at the level of the collar (dry application), not to slow down the installation of beneficial populations of microorganisms in the substrate.

Conversely in open soil growing, Silicate’s composition stimulates the growth of helpful microorganisms and helps create a beneficial natural environment for extremely healthy plants.
 
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