There are tiny black crawling insects on our Gardenia flowers. Not on the plant itself or buds just on the open flowers. I have sprayed with NEEM and Sevin. The problem is that they are only on the flowers as they bloom. They may even be flying insects but they are almost microscopic and appear to be crawling on the flowers. These are mini Gardenias and each flowers has an abundance of these black bugs.
Certified GKH Gardening Expert
If you can include a photo, it may help me to identify the pest. This sounds like a few different pests. Most can be killed off with home-made pesticides, however.
This collection of articles will give you ideas on how to craft your own pesticides, along with many other articles that will help: https://www.gardeningknowhow.com/special/organic