Answer: Hibiscus will do this when the plant is over or under watered. The older leaves (those farthest down the stem) are usually the first to go. The symptoms are often delayed a bit after the water stress conditions. So you may have recently watered but still see the problem. Overwatering contributes to root loss from lack of air and is often complicated by an ensuing root rot. This situation can result in a long term setback for the plants. Lack of nitrogen can also cause a gradually loss of the green color in older leaves, but such symptoms are different from the sudden yellowing and dropping most often encountered. You might might dig down into the soil to see how moist or dry it is down around the root mass. The soil should be damp but not overly moist or soggy wet. Once you have an idea about how deeply the soil is getting moist you can adjust your watering schedule to better suit the plant. Good luck with your hibiscus.
Q&A Library Searching Tips