[]If the rain doesnt come after applying granules to the lawn the pellets rest on th eleaf base. The sun comes out and scortches the leaf turning it yellow. either water after application or use a liquid lawn feed. see www.superspray.co.u for liquid and sprayer. It may be the cause. Not sure you can overdose with these pellet feeds unless you go over and over the grass. I would give it a liquid feed only every two weeks from now. You can try seaweed extract which willstrengthen the root cell strucure rather than just green it up.