Roots Organics Nitro Bat Guano is an excellent source of nitrogen, phosphorus and calcium. Carefully processed and sifted to make it easy to work with, Roots Organics Nitro Bat Guano encourages vigorous growth and is fast acting for quick results. All of the Roots Organics guanos have been carefully sourced for quality and harvested with bat-friendly methods so you and your garden get performance with principles. 100% naturally occurring bat guano. No additives. No filler.