Grotek® Gro-SilicPLANT RESISTANCE With a high concentration of soluble potash and silica, Grotek Pro Silicate was developed for use in soilless media and hydroponic systems where these elements may be lacking. While not considered an essential nutrient, plants accumulate silica in macro proportions for good reason. Silica is known to strengthen cell walls and overall cell integrity, which makes plants more resistant to abiotic stress such as heat and drought.