I had a beetle-like bug eat my hibiscus blooms and leaves this summer. I think it might have been a form of weevil. It was about 1/2" long, dark brown to black. This bug would fly away when provoked. They ate into the flower pods eating them before the blooms opened. Also, they ate/burrowed the seed pods hollowing out the seeds. I raked out the mulch underneath my plants, did a high pressure water wash, then applied Sevin on the plants including the soil. I did that twice and now my hibiscus are bug free and blooming wonderfully. My hibisucs is perennial, called "moy grande".