hibiscus is having difficulty indoors
I brought my hibiscus plant in for the winter and I have begun to notice small black spots (not bugs) on the petals of the flower. I can rub the spot off. Now the buds are not opening all the way. What are the spots and what can I do to remove them?
I'm guessing your hibiscus has thrips. The small black dots that you can rub off are the thrips' fecal matter. If you look very closely deep inside the flower petals, you'll probably see some tiny, flea-like bugs, white or black - those are the thrips. Thrips are hard to control because they are deep inside the flower blossom. Probably the best thing to do is first to cut off and dispose of all the flowers and buds. Then you can spray with neem oil in case there are some bugs still hiding in the foliage. This article has more information on thrips control: https://www.gardeningknowhow.com/plant-problems/pests/insects/controlling-thrips.htm