Rare Earth, from General Hydroponics, is a premium blend of dry organic minerals and humates that is derived from ancient seabed deposits of pyrophyllitic clay that are blended with fulvate ore. 

By slowly releasing silicon, humates, and organic rare earth minerals, Rare Earth allows a crystal matrix to develop within growing plant tissue that protects the plant from heat stress and nutrient extremes by generating a protective silicon shield.

Rare Earth also deters fungal disease and reduces susceptibility to insect damage by "hardening" the plant.

Use Rare Earth by blending it with rooting media, and either top-dressing around the plant stem or adding it directly to nutrient solutions.