I have found that hibiscus are heavy eaters and need lots of fertilizer. I use Miracle Gro Bloom Booster and that works well with mine. I have three around three feet high and one that has been trained into a tree and they all seem to like it. All are in pots, however one is taking a long time to bloom this year. Their blooms are lovely but they are tempermental and prone to white flies and sometimes I wonder if they are worth the effort! I usually fertilize twice a month using a tablespoon for each gallon of water. Hope it helps. I'm in exteme southern GA.Flossieann.

Thanks for the info bought some the other day. Hope that it helps i know it won't be immediate, but we shall see what happens