12d65980_ening_Tips_and_Plants___How_to__Plant_Symptoms
[Deficiency] Sulfur [Plant Uses] Found in amino acids, vitamins and co-enzymes [Sources] Manure, Sul-Po-Mag, gypsum, elemental sulfur [Plant Symptoms] 
Leaves at branch tips turn down Stems are hard and brittle
Organic Gardening Tips and Plants - How to