A reader asks today if I would have the answer to the reason why the leaves on her Hibiscus are turning yellow. She asks, Could it be that she is watering them too much? I ask myself here, can one really water too much in the summer months? She doesn't mention if the plant is in a pot or in the ground because that may influence the situation a little. In the ground the water naturally drains away or dries out in the sun where as a pot in a drip plate could easily be sitting in water all the time. Remember all leaves do fall at some time or other, some as in deciduous trees and shrubs loose them all about the same time in the autumn where as others stay green all the time just letting fall a few at a time which could well be what is happening with this Hibiscus. Just keep an eye on it, should the stems with the yellow leaves look damaged then cut that stem back to where it looks healthy, even to the main stem to avoid any 'die back'. It doesn't hurt to do a sort of summer prune when some shrubs grow beyond themselves just to tidy them up a little and encourage more flowers to form on any new growth. At the moment the Hibiscus is one of those shrubs that is in full flower with many new varieties in quite different colours , the brightest yellow or salmon pink as well as the brightest red.