- What is Silicon?
- Forms of Silicon
- Affects on Plants
What is Silicon?
Silicon is considered a non-essential plant nutrient which means this element is neither a macronutrient or micronutrient for cannabis. Even though silicon is non-essential, it is still a very beneficial nutrient for cannabis plants for vigor and growth. Silicon should not be confused with Silicone which is a synthetic polymer made up of silicon, oxygen, carbon, hydrogen, and other elements. More importantly, there are different types of usable silicon a plant can utilize and some are more bioavailable than others which can affect the plant differently. The two different forms of silicon are silicic acid and silicate.
Forms of Silicon
Product suppliers and cannabis growers may use the term silica to describe silicon products, this is because the term silica refers to compounds of silicon plus oxygen. There are two types of silicon products that are commonly applied to the grow medium by cannabis growers and they are silicic acids and silicates.
- Silicic Acids: compounds containing silicon (Si), oxygen (O), and hydrogen (H) including monosilicic acid Si(OH)₄ or orthosilicic acid.
- Silicates: compounds containing oxygen and silicon as well as other elements such as potassium (K) and Calcium (Ca). This includes calcium silicate and potassium silicate compounds. Products containing compounds of silicates are usually considered silica products.
Silicon is taken up by plants as silicic acid via aquaporin channels. Most growers recommend monosilicic acid for the best silicon related results as this form of silicon is the most bioavailable for plants when compared to silicates.
Affects on Plants
Silicon provides a number of benefits to cannabis plants. Some of the benefits include increased resistance to pests and pathogens, increased growth, and increased stress tolerance. Silicon helps increase the resistance to abiotic stresses such as salt stress, drought, and heavy metal exposure. An increase in resistance to pests and pathogens occurs in part through silicon’s ability to fortify the cell wall of plants which prevents fungal hyphae penetration. Not only that, but silicon also increases a plant’s defense responses similar to a systemic acquired resistance (SAR) through an increase in chemical signaling in plants.