Hibiscus plants (Hibiscus rosa-sinensis) are tropical plants that thrive in frost-free gardens and as potted plants. They require plenty of sunshine and regular watering to thrive. Hibiscuses produce large, showy flowers almost all year-round but are vulnerable to overwatering, especially in the winter. You should always check hibiscus plants before watering as continually wet soil damages them and prevents flowering.
Symptoms of Overwatering
Overwatered hibiscus plant develop yellow leaves that drop off the plant. They may also lose flower buds and grow very slowly or not at all. Stressed hibiscus plants are also more vulnerable to infestations of bugs, such as mealybugs and aphids. Long-term overwatering causes root rot and kills whole plants.
Check the soil of an ailing hibiscus. Turn potted plants upside down and tap the container to remove the root ball. If the soil is completely soaked down to the base, do not apply any more water until the top inch has dried out completely. If the bottom of the soil is dry, then your hibiscus needs more rather than less water. Provide enough to thoroughly soak the soil every time you water. Monitor the ground around outdoor hibiscus plants to make sure it is not waterlogged.
Treating the Problem
Withhold water from a hibiscus that has been sitting in waterlogged soil until the top inch of soil is completely dry. Place potted plants in a bright location exposed to direct morning sunshine to encourage evaporation. Remove the berm from around garden plants to prevent water from gathering around your hibiscus. Make sure that automatic sprinkler systems do not water hibiscus plants with wet soil. Consider transplanting a hibiscus plant that grows in continually wet soil.
Always check the soil before watering your hibiscus plant. Water when the top inch is completely dry. Provide less water during the winter when hibiscus plants grow slowly or enter dormancy. Aim to moisten rather than soak the soil during the winter. Never leave potted hibiscus plants standing in a dish of water and make sure that the drainage hole in their container is unblocked.