Using a silicon additive in your grow

Silicon – The Plant Strengthener

Growth Technology Liquid Silicon

Silicon additives have been around for quite a while now, and the benefits they bring are pretty much indisputable: stronger stems and branches, better resistance to dry conditions, plus better resistance to insects and fungi that must first puncture the surface of the plant in order to feed and take hold. Basically, if you’re not using silicon then you should seriously consider trying it as one of the next additions to your grow.

Silicon is naturally found in soil (in small amounts). Although it’s not actually an essential nutrient, if plants have access to it, they will use it to strengthen their stiff cell walls and the joins between them. If you take 2 otherwise identical plants and treat them exactly the same but give one of them a silicon additive, after 2-3 weeks the difference between them will be immediately obvious.

How Silicon Affects Plants

Humboldt Nutrients SI

The plant that has been fed silicon will look like it has been body-building, with a much thicker main stem and branches. This makes a big contribution toward the end of the grow when the plant has to support it’s heavy fruits or flowers. Going down to the microscopic scale, the cell walls will be thicker and stronger, as well as the connections between them. This makes the plant unattractive to pests that bite or pierce the plant in order to feed, because it gives them a really hard job.

Because the cell walls are tougher, it makes the plant more resistant to damage. For most species of plant, apart from the obvious benefit of having undamaged and healthy plants, a fantastic side-effect of this is that unwanted fungal infections find it much more difficult to take hold. Botrytis (aka the dreaded grey mould) most often gets into a plant via a damaged part. Plants without any damage are difficult for botrytis infect. Likewise powdery mildew.

Plants treated with silicon transpire less and can uptake and use water much more efficiently. This gives them a higher survival rate in drought conditions (not that anyone ever forgets to water their plants, of course…).

And There’s More….

Shogun Fertilisers Silicon

With all those benefits, you’re probably wondering why anyone would grow without it. But we still haven’t got to end of the list yet! In fact I have left probably the best bonus until last. That is that silicon increases the rate of photosynthesis. Yes, that’s right. Silicon actually stimulates greater chlorophyll production, and chlorophyll is the compound in the plant that conducts the photosynthesis. More chlorophyll means more photosynthesis. The higher the rate of photosynthesis creates more sugar. The greater amount of produced sugar then powers more growth and improves the quality and numbers of fruits and flowers.

So, are there any drawbacks? Well, there’s just one small inconvenience. Silicon needs to be added to your feed water in a specific way in order to avoid causing precipitation (cloudy water) when you add you main nutrient.

How To Use A Silicon Additive

The correct way to do make up your feed water / nutrient solution is as follows:

1) Use reverse osmosis water or tap water that has been allowed to stand for several hours to allow the chlorine to evaporate off. This is particularly important if you grow organically, or make use of beneficial bacteria and fungi. Even better is if you bubble air through it (via air pump and airstone) while it is standing, in order to oxygenate it fully.

2) Mix in your silicon additive at the recommended dosage for that product. The pH will usually go up. There is an exception to this – Rhino Skin by Advanced Nutrients does not raise pH.

3) Using a pH pen and pH Down product, bring the pH of the solution down to just below 7.

4) Add your nutrient and any other boosters.

5) Using your pH pen and pH Down product, adjust the pH to the correct level for the type of grow you do. (pH 5.5 – 5.8 for hydroponics). This step may not be required if you grow in soil.

If step 3) is not followed then your nutrient solution may go cloudy indicating that precipitation has occurred, making the silicon unavailable to the plant.

Which Silicon Additive To Buy?

There’s lots of great silicon additives on the market. 3 of the most popular with our customers are listed below:

Shogun Fertilisers Silicon 1 Litre

Humboldt Nutrients SI 473mls

Growth Technology Liquid Silicon 1 Litre

However, also worthy of note is Advanced Nutrients Rhino Skin which is part of their “pH-Perfect” line-up and does not alter pH:

Advanced Nutrients Rhino Skin 1 Litre

Advanced Nutrients Rhino Skin