Determining the cause of bud drop, will be rather like sleuthing. There are a number of reasons this could happen and you will need to discover the cause through planned trial and error.
If your hibiscus is losing leaves, it may be stressed from disease or parasites. This is a page about hibiscus losing leaves.
This is a page about hibiscus leaves turning yellow. Yellowing leaves on a plant can indicate a number of issues. Identifying the cause will allow you to treat your plant.
This is a page about pruning a hibiscus. Knowing the best time to prune your flowering shrubs can not only improve their shape, but will not disrupt their blooming.
Know what to do to when a shrub has been damaged by a hard winter. This page is about hibiscus damaged by cold weather.
The hibiscus is a deciduous shrub that can provide lots of garden color during the summer. This page is about hibiscus not growing.