When used as fertilizer, kelp makes plants more robust and healthy by enhancing their heat, drought and cold tolerance. In addition, kelp increases the plant growth rate and fruit production, size, and quality. Potassium must be present in large quantities in plants because it is a component of the fluids which flood the plant tissue. Potassium-deficient plants are susceptible to insect attack, have weak stalks, and underdeveloped root systems. Sufficient potassium produces high quality vegetables and tree fruits.
Sulfur is often present in plants in equal or greater amounts than potassium.
Sufficient sulfur produces high quality and yields of vegetables, tree fruits, small grains, legumes, and forages.