I use Osmocote Plus on my hydrangeas and they bloom beautifully. Shrubs and trees don\'t usually need as much added fertilizer as vegetables, perennials and annuals but as hydrangeas make flowers as well as foliage I like to make sure they are well fed. I sprinkle an application around the drip line of the hydrangeas where the feeding roots are located. The dripline is where the ends of the branches are - where water would drip if it fell off the tips of the branches. Keep growing, Marianne Binetti