I was using Miracle Gro Bloom Booster for all my flowering trees the #'s are 15-30-15 and I diluted 1/2 recommended strength( 1/2 teaspoonto a gallon of water) watering with it every 2 weeks.Living here in Pa now my tree's are indoors for the winter months. My girlftriends tree (Flora-Plena) Double white rose to a spill in early spring and had to do a replant so it didn't or wasn't blooming as much as my tree which is the Pink Double rose (Ahiro-pink). Mine is still blooming a good bit and hers has a couple blooms on it. I would have to say my Serrisa aren't as finky as I have heard and read but knock on wood maybe I'm just lucky. I have them under a 4' shoplight on a 16 hr timer. Jes