Epsom Salt (Magnesium sulfate) 50 lb

Organic (OMRI)

Source of readily available magnesium and sulfur; fully soluble and can be applied through irrigation or used in hydroponic systems. 

Most Willamette Valley soils do not require magnesium supplementation; gypsum (calcium sulfate) is a better option in most cases, unless indicated by a soil test or supplementing a soil-free growing medium.