Sulfur

sulfur deficiency will sprees itself all-over as chlorosis (yellowing of leaves), usually starting with the newer leaves, first may look like a nitrogen deficiency.

The parts underneath the leaves may take on a pinkish red or orange color. The buds on a flowering plant may start dying. Unlike most other deficiencies that cause chlorosis, a sulfur deficiency will start at the back of the leaf and move it's way forward. check and correct your pH to make sure that your sulfur isn't being locked out. Sulfur moves slowly through the plant so it may take a few days after you fix the problem before you start noticing an improvement in your plant.