Bush Doctor® SledgeHammer® is a unique rinse formula designed to remove excess fertilizer build up by encouraging water movement through soil and soilless media. High fertilizer use can compromise plant growth over time due to concentrated mineral salt deposits. SledgeHammer® is a unique rinse formula designed to remove fertilizer buildup which may relieve nutrient lockout. Derived from saponin, an extract of the Yucca schidigera plant. SledgeHammer® is designed for organic gardening and can be used for both hydroponic and soil applications.