Question: I have an old hibiscus tree indoors. Its in a cool room and gets indirect sunlight. It now has started to drop leaves and hasn’t bloomed for months. I only water it when it gets dry. Do you think I need to repot it?
Answer: Our hunch is that your plant isnt getting enough light. One half-day of direct sunlight from a bright east or south window is best for promoting flowering and keeping leaves green and healthy. Another problem could be insects. Check the bottom side of the leaves and the stem. Hibiscus will tolerate a broad range of temperatures (60°90°F), but may not flower if too cool. Fertilize every other month with a fertilizer high in potassium (K). Vegetable fertilizers work well. Repotting certainly wont hurt, but that probably isnt the problem.
–Gardening experts George and Becky Lohmiller, Hancock, New Hampshire