My hibiscus looks healthy, but there are no flowers coming anymore because when the bud is very near to open, it falls like it was cut with a perfect saw cut. I have seen some leaves with round holes (as eaten), and I noticed an insect with round, roughly shape brown color. What I can do to restore the capability to have flowers and kill the insects?
Certified GKH Gardening Expert
Try neem oil. It's good for many types of insect pests. Here is more information: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm