Question: Do Hisuscus like an acid soil? Would it be appropriate
to use pine needles around them?
Answer: Hibiscus adapts to the pH of most soils. A mulch of peatmoss or pine needles will be beneficial in helping hold soil moisture and suppress weeds, and doing so won't change the pH to any great degree.
Q&A Library Searching Tips
When singular and plural spellings differ, as in peony and peonies, try both.