From Grow Magazine , July 2018; Sustainability Issue

BY CHRIS KEHOE

Silica is widely misunderstood. It is mistakenly left out of most plant nutrition and agriculture input management programs. Current popular wisdom for adding silica (SiO2) to any cannabis nutrient regime is relatively limited to strengthening cell walls and increasing vigorous plant growth. Fortunately for growers who are ready to master the art and science of cannabis cultivation, the role of silica is just now being discovered for optimizing success in plant nutrient programs.

Modern plant science classifies silica as a beneficial micronutrient required for healthy plant growth. Silica is a naturally occuring compound containing the elements Silicon (Si) and Oxygen (O), known scientifically as silicon dioxide [SiO2]. In order for plants to benefit from SiO2, silica must be plant available in forms such as silicic acid [Si(OH)4] or Monosilicic acid [H4SiO4].

Historically, most soils had some soluble forms of silica as a result from physical and geochemical weathering. Due in part to climate change and unsustainable farming practices, plant-available silica in native soils is increasingly ra