4fcb4a28_Quick_Guide_to_Plant_Nutrition__Signs_of_Deficiency
[Primary Nutrients] Sulfur (S) [Function in Plant] Synthesis of proteins; involved in photosynthesis and enzyme activities [Sources for Fertilizer] Gypsum Epsom salt [Signs of Deficiency] 
Stunted or reduced growth; paling or yellowing of leaves, particularly new leaves; purpling of leaves or leaf edges
A Quick Guide to Plant Nutrition
Signs of Deficiency