Fertilize in the fall, September- October with organic fertilizers, or as late as mid-November with slow-release synthetic. This feeds fall and winter root growth, as the plant stores nutrients for the next growing season. If you want to fertilize in spring too, wait until spring growth slows in May.

Thatch Removal It's usually best to dethatch before the middle of April. If you don't realize that you have a thatch problem until mid-summer, dethatching can be done after the hot weather passes in September.