espoma btsp4 4 lbs bio-tone® starter plus 4-3-3 espoma io-active plant food with beneficial bacteria, humates plus mycorrhizae. for enhanced root development. 100% natural and organic approved plant foods. the tone products are made for complex blends of the finest natural and organic ingredients. no sludges or fillers are ever used. they are enhanced with bio-tone beneficial microbes to help plants establish fast, develop deeper roots and have superior blooms. consistency and quality are guaranteed. long lasting results - won't burn or leach away.