Q: I purchased two hibiscus trees this year and placed them on my hot, sunny decks. One of them has lots of flowers, but each day more and more leaves turn yellow and fall off. It’s starting to look like there will be no leaves left soon! The second hibiscus has no flowers and the same problem with the leaves. What do I do? I am starting to panic, as they looked so pretty on the decks, and I really want them to live. I was hoping to be able to bring them in for the winter.
A: Hibiscus trees or plants aren’t the easiest plants to grow in our climate — even indoors. Let’s start with the pots on the deck; a perfect place for the tropical plant, assuming there’s sun all day. You brought them home from a greenhouse or an indoor shop and you don’t know how they were cared for, so now it’s all up to you. The hot weather is perfect for them — keep them well watered. If the plant has more than a few leaves that are yellowing, a bug may be the suspect, so get out the garden hose. Spray every leaf on every side, every week or two throughout the summer. In the winter, put the plant in your shower every week or two; spraying will knock off any bugs and raise the humidity.
Fertilize the hibiscus regularly when it’s growing. Remember that a hibiscus plant blooms on new growth; trim gently when necessary. In late summer, plan to bring the plant inside next to a very sunny window, but even this might not be enough sun; artificial light may be necessary. Summer or winter, never allow plants to stand in water.
Q: One of my favorite things about summer is my endless blue hydrangeas. This year I have lots of blooms, but they are smaller than usual. I admit I did not fertilize it, but could that be why the flowers are so much smaller?