Answer: My first thought is that a bud worm is ruining the buds before they have a chance to open. This little worms are the same green color as the foliage, stems and unopened buds on a hibiscus plant which makes them difficult to detect. However, they make a hole in the sepals of the unopened flower and feed inside the flower. To see if your hibiscus has these pests, closely inspect the unopened buds to see if you can find a small entrance hole. Or, open the unopened buds and look to see if all the flower parts are intack. If you see worm damage, you can spray your plant with Bt (bacillus thuringensis) which is a botanical that acts as a stomach poison and is very effective in controlling caterpillars.
Best wishes with your hibiscus!
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