Hibiscus are outdoor plants (south Texas), in the sun for 2/3 of the day, get plenty of water but they hardly flower.
what kind of hibiscus are they tropical or hardy. than what type of fertilizer do you use. allot of the tropical hibiscus will bloom more after being trimmed. there are several acceptions the only one i know for sure is the schizopitalus/skelenton flower. and some of the hybrids from that one they bloom more if left untrimmed for as long as you can. the fertilizer i use on all my plants is formulated for my area cannot remember the numbers but it is mainly for fruiting plants and it has minors in it. just make sure it is a good fertilizer not a cheap 6-6-6 that has mostly chlorine for filler. there are some decent brands of 6-6-6 but the point is cheap is not always good. choose whatever numbers are recomended for you're area. i cannot give to much advice on the hardy hibiscus most of the hibiscus i grow are the tropical i gave up trying to grow the hardy hibiscus in my area.
