Hibiscus buds can take bit longer than other flowers to open, however, I have one hibiscus that is especially picky and if conditions aren’t just what it wants, it ends up dropping it’s buds.

In the heat they want to be watered every day, or even sometimes twice a day, and they like shelter from the hottest afternoon sun.

Another thing to consider is that hibiscus are picky about their feeding, not just any old 10–10–10 fertilizer is going to work.

Check out some of the fertilizers here, and the care page. I’ve learned so much from this website - Fertilizers & Nutrition