Roots Organics phos bat guano is an excellent source of phosphorus & calcium. Carefully processed & sifted to make it easy to work with, Roots Organics phos bat guano encourages vigorous flowering & fruiting. All of The Roots Organics guanos have been carefully sourced for quality & harvested with bat friendly methods so you & your garden get performance with principles. Roots Organics 100% naturally occurring bat guano. No additives. No filler.