It seems that every week a nutrient manufacturer releases a new silica product onto the market, each one claiming that their silica is the best. Personally, I find that when I sell silica products, customers are confused as to their purpose and application. I want to try and clear it up some of the confusion.
The purpose of silicas is to make plants stronger, more drought-tolerant, and healthier. Silicas also help protect against diseases and pests. In my experience, when used correctly, silica products do exactly what they claim; your plants will generally be healthier when silica is used correctly.
Silica content and quality can vary heavily based on its source, trace elements, and its effects on plants. They can be derived from a variety of different sources such as monopotassium silicate, silica dioxide, or salicylic acids. Some are also derived from trace minerals such as azomite or sand. One of the recent silicas on the market is Harvest Gold, which stands out to me because it is the only silica that contains trace gold content. Some have higher concentrations of boron and/or molybdenum. Different silicas are readily available for plant roots while other silicas take time to absorb.
I’ve tried virtually everything on the market. I used Aptus’ Fasilitor for several years and was quite impressed with the results. Osa 28 produced similarly strong plants. The only problem was that both of these products had a hefty price tag. A liter of Fasilitor retails for $474 and a 32 ounce of Osa 28 retails at $285 on the Growers House website. On the other end of the pricing spectrum we find Armor Si from General Hydroponics, Silica Blast from Botanicare, and Pro Tekt from Dyna Gro. All of these latter silicas retail for under $20 bucks. This seems like a pretty broad price spectrum for products that all claim to have the same results.
I would like to know what other growers’ experiences have been with silica products. What silica do you use and how? Why, in your estimation, is your silica superior to the competition? Let’s try to clear up some confusion surrounding silica!
I always suggest going by manufacturers recommendations when utilizing any
new product into your current nutrient regimen, however when it comes to
liquid silicas, the order in which one mixes is absolutely imperative. The
standard for mixing liquid silica when part of a drench is to mix the
silica in first, aerate for 10-30 minutes to allow for your H2O to become
hydrophilic, then proceed to mix your nutrients as you normally would. You
should see stronger plants and healthier internodes rather quickly.
Hope this helps, drop me a line with any other questions you may have!
Armor Si from General Hydroponics is a great potassium silicate with 10% silica dioxide. Priced at under $15 ($13.62 per quart on Growers House website), this silica can definitely help make stronger plants without breaking the bank. Make sure you add this silica first and let it circulate in your reservoir prior to mixing nutrients. If you ever have doubts as to the efficacy of any product, I recommend doing a side-by-side test on plants with which you are already familiar: add the product in question (in this case General Hydroponics’ Armor Si) to one plant and leave the other plant alone and feed as you would normally. If you notice a significant difference in the plant given the Armor Si, I would consider integrating the product as part of your normal nutrient regimen.
I actually use Armor Si from General Hydroponics as well (I home grow in full disclosure, not commercial.) I’ve also used Silica Blast (loved both products to be honest.) In the past I hadn’t used any silica products at all with my growing and finally decided to give a bottle a shot (it was explained to me in laymen terms that it “just provides some extra resistances to the plants that otherwise wouldn’t be there, allowing better growth in environments you otherwise didn’t even realize there were environmental problems.”)
I hate to say “night and day” difference but there was a very visual distinction between how thick the stems got versus not using it, how hardy the plants grew, etc, using the same setup and same environments I always grow in.
Can you explain a bit on why it’s necessary to add the silica in first before other additives? What would cause the silica to mix improperly if other nutrients/additives are put into the water first?
Also with your experience with it @Growernick , would you say there are better times to add silica in during growth or during all stages of growth? At some point in time do you suggest not feeding it to the plants out of not being utilized efficiently? Manufacturers recommendation? Growers choice?
Armor Si and Silica Blast are quite similar in their composition so it
makes sense that you achieved similar results using both products. We add
silica first and aerate the solution to increase hydrophilia in the H20 and
to help with nutrient buffering. It’s worth mentioning here that you never
want to simultaneously mix Calcium/magnesium with silica as it will cause
the mix to precipitate.
I’m happy to hear that the difference was “night and day” between your
control and variable groups! The first time I used a silica I found the
results to be similarly astonishing; thus I was hooked. I have since spent
the last several years trying out all the silicas on the market and I am
excited when new silica products emerge. I’m super stoked to next try the
silica line brought to market by Harvest Gold.
I start withholding silica around week five of flowering. Silica has a
longer half-life than some other micro nutrients and macro nutrients so I
want to get it out of the plant system a little earlier than the final
flush.
Hopefully these posts demystify and clarify the use of silicas for folks.
Thanks for the question and the compliment!
Thanks growernick for including % SiO2. This can’t be ignored. I like to approach the value of each product by price per unit of product (in this case SiO2)
At quart prices you are paying ~$0.14/mL of pure SiO2. You can’t exactly use mL like this but bear with me for this example.
I use Sil-Guard, which goes for ~$60 for 2.5 gallons @ 7% SiO2
That’s $60 for 9,460mL @ 7% = $60/662.2 mL of SiO2 $0.09 per mL of SiO2
How each product affects your total fertilizer regimen also has to be accounted for. Definitely pay attention to the macros, but I do wonder if the gold/molybdenum levels will really make an appreciable difference. I’d love to hear one way or the other, but most micros are obtained through other means.
Thanks for adding that info! I will provide meaningful data as we move forward with the study update posts, especially if we see significant difference from the increased Mb and Au.
Wettable micronized diatomaceous earth works great as do rice hulls for natural sources of silicon. These work just as well as potassium silicate in my experience.
Never would have even thought of using diatomaceous earth for that purpose. How do you apply that @AmericanWeedwolf ? I’ll top dress my pots with it depending on the problem (or put it into a spray bottle,) curious if there’s a method you’ve used?
And rice hulls for silica? I had a buddy ask me to try them out in place of perlite (essentially providing the same benefits he said but they naturally break down (and no perlite dust, which is pretty awful I’m sure you know.) Will have to look that up, that’s really cool!
Funny story about the rice hulls, when I did finally try them out I didn’t know where to source them local/cheap. Had this bright idea “oh, well I’ll just go to the home brew store and get some (I home brew beer as well.)” So I go into my favorite shop (little hole in the wall place,) and I LOAD UP. I mean I cleared him OUT! And I get up to the counter and he says to me “WOAH, whatcha brewing today?” When he found out what I was doing, I got a bit of a butt chewing and told “next time give me fair warning and I’ll bring in 55 lb bags for you.” Good stuff, good stuff.
Jordan, micronized D.E. can be pre-mixed, top dressed, or mixed in water and applied as a liquid suspension (mix well) for foliar spraying or as a soil drench. Rice hulls are so rich in silica, they are even beginning to be used as a (sustainable) industrial source of the element in the production of microchips and photovoltaic (solar) panels! The silica in both are not extremely water soluble, but they should provide plenty from your plants’s perspective!
As a side note, stinging nettles and horsetails are other good natural sources of bio-available silicon, if you have a patch growing nearby, they work great in the compost pile or brewed into tea that can be applied as a foliar spray or soil drench as well!
Silica is the most common element in natural dirt. But most of us grow in a specialized substrate or even hydroponic ally, which usually contains no Silica.
I’ve been adding azomite dust to my potting mix with great success. If purchased from a farm supply company and not a cannabis specialty store, it’s relatively cheap. The last 40lb bag that I bought only cost around $50. The problem is you need to figure out your own optimum application rate so you don’t waste it.
I’ve consistently used Pro Tek on everything from orchids to lilikoi. Lol. It really does strengthen seedling stems. But I discontinue it at the first replant because it can cause nutrient lock out. Also, be aware that it will cause a lot of common nutrients to chelate out of solution. So mix small batches at a time to avoid a sludge forming in your mixing tank.
He speaks the Truth! Silica comprises 27% of the Earth’s crust, making it one of the most abundant elements on the planet. For agricultural purposes, silica strengthens the cell wall in the plant tissue. Think of silica like a layer of bubble wrap between the cell walls adding a protective barrier that strengthens the whole plant system.
Be very cautious when mixing any soluble silicas (i.e. those derived from silica dioxide or potassium silicate) in your hydroponic reservoir, as there is a proper way to do it, and mixing wrong can bring on a host of adverse issues. Always mix your soluble silica first in your reservoir and let it aerate for 10-30 minutes. I always recommend feeding the silicas separately (i.e. standalone) from other nutrients to prevent lockout from occurring. Also be aware that adding silicas with cal mag can cause the solution to precipitate. You DEFINITELY don’t want to feed that solution to your plants!
Pre-amending a granular silica like Harvest Gold Silica or azomite can help accomplish the same results as a liquid soluble with the ease of only amending with each transplant. I love your suggestion and the info!
I may need to start a new thread but I just wanted to ask whether anyone has looked into lithium and cannabis.
Doctors are finding that in areas with a low lithium level in the water or in their root crops, there is a higher incidence of bipolar disorder.
Like Silica, lithium is readily available in soil but is it a plus, minus or push when applied to growing cannabis?
Definitely worth looking into! Lithium has long been used to treat individuals with bipolar disorder, and it has a long half-life in plant tissues. With those facts in mind, it stands to reason that its residual presence in cannabis would lead to higher incidence rates of bipolar disorder. Interesting indeed! Please share any findings you might uncover!
When he found out what I was doing, I got a bit of a butt chewing and told “next time give me fair warning and I’ll bring in 55 lb bags for you.”