HibisGain 12-6-8 is designed for hibiscus and other flowering plants. BGI makes a product called PalmGain that is more appropriate for palms and similar tropical greenery. Many wasp killer sprays are quite oily, so spraying an oily product on plants on a hot, sunny day could potentially cause burn on the plants. Be sure to follow the directions on any products you are using near desirable plants.
Yes, HibisGain 12-6-8 Plus Minors can be used on perennial hibiscus plants.