I would like to know of any real advantages or disadvantages to using silica in a hydroponic fertilizer solution. I know it is taken up by the plant through the roots and integrated into plant tissues such as naturally in blades of grass, but does it provide the claimed benefits of improved growth, nutrient uptake, stress, and drought tolerance? Moreover, would it be safe to consume in lettuce and smoke in tobacco for example?
Check this articles:
Effect of silicon in the nutrient solution on the incidence of powdery mildew and quality traits in carosello and barattiere (Cucumis melo L.) grown in a soilless system
http://www.jhortscib.org/Vol84/84_3/10.htm
Silicon biofortification of leafy vegetables and its bioaccessibility in the edible parts
http://onlinelibrary.wiley.com/doi/10.1002/jsfa.7142/abstract;jsessionid=6F542B2F9AFF89A7E45732AE2C24E642.f04t01?userIsAuthenticated=false&deniedAccessCustomisedMessage=
Potassium meta silicate is/was used in the Dutch horticulture soilless industry (via a separate tank), but only for crops like roses and cucumbers. The main benefits seems to be the better resistance against powdery mildew, probably related to stronger cell walls.
I used silicon against to salt stress on pepper plant. I carried out the pot experiment. I used as substrate vermiculite. I determined the effect of reducing the silicon salt stress but I didn't write article yet.