Several types of hibiscus plants are native to Florida, and caring for them is essential to their health. Native hibiscus varieties include scarlet rose mallow, comfort root, and swamp rose mallow. These plants can grow to be four to eight feet wide and up to fifteen feet tall. Although hibiscus native to Florida are much better able to survive cold temperatures than those native to more tropical environments, any hibiscus will thrive in Florida if given proper care.
Hibiscus plants in Florida are usually resistant to insect and disease infestations as long as they are healthy. However, those plants that do get infested with insects in Florida are most usually victims of the hibiscus sawfly, whose caterpillar-like larvae eat hibiscus leaves. Whiteflies, spider mites, and mealybugs can also infest hibiscus plants. Insecticidal soap and sticky traps can be used to control these populations of insects, or the plant can be taken or left outdoors if the weather is expected to drop below freezing overnight. Often, a light frost or freeze will kill insects without killing the hibiscus.
Hibiscus plants wintering in Florida often suffer frostbitten leaves and stem ends if the weather gets too cold at night. Because the temperature and amount of frost that forms on a plant depends in part on the shelter it receives from other plants, buildings, or fences, some hibiscus plants may be frosted while others survive a cold night unharmed. Leaving the brown leaves or stem ends on a frosted hibiscus can help insulate the plant against further frosts. If no further frosts are expected or the brown leaves are unbearably unattractive, the plant may be pruned. Hibiscus plants in Florida do best when pruned after they have begun putting out new growth in the spring.
Although Florida's mild temperatures allow hibiscus to be planted year-round, planting hibiscus in the spring or summer gives the plants the best chance of survival by allowing them to establish strong root systems and store food before winter sets in. Planting hibiscus during a Florida winter, on the other hand, risks frost damage to the young plants.