Hibiscus Is Green But Not Growing Back After Freeze

Perennial Hibiscus

• Perennial hibiscus varieties like swamp rosemallow (Hibiscus grandiflorus), scarlet rosemallow (H. coccineus) and Confederate rose (H. mutabilis), among others, die back to the ground with the first frost, but new shoots will emerge in spring. The plants are not truly perennial, they are hardy herbaceus perennials -- meaning that if the winter temperatures are extremely harsh, the roots will freeze and the plant will not come back in the spring. Hardy hibiscus are grown throughout the southeastern United States but will not tolerate conditions in northern climates. If your hibiscus is green after exposure to the frost, the best that a grower can do is wait. Once temperatures warm, you will notice that the plant will either continue to grow without blooms or the branches will turn brown. A hardy hibiscus may not grow or bloom during the current season, but it will sprout and bloom again the next spring.

Annual Hibiscus

• Unlike perennial hibiscus, annual hibiscus grow, flower and die within one growing season. Annual species like Chinese hibiscus (Hibiscus rosa-sinensis) and red leaf hibiscus (Hibiscus acetosella) are less frost tolerant than perennial varieties, and are less likely to withstand temperatures below 40 degrees F. Again, the plant may retain its green color for several weeks, but ultimately it will turn brown and die back. In the event that the plant does retain a green color, it is not likely that it will produce blooms at all, or as well as hibiscus that have not undergone similar stress.

Care

• A perennial hibiscus will likely recover from frost damage when it receives low-nitrogen fertilizers and is supplied with enough water to keep soil moist. As a response to cold, the plant will send out excess shoots and minimal blooms. But, when given the fertilizer, four to five hours of direct sunlight and bloom-boosting fertilizer, your hibiscus should bloom again by midsummer.

Maintenance

• Maintain hardy hibiscus and encourage new growth by cutting back brown stems in early spring. Leave the brown stems and leaves on the plant throughout the winter months, as these old branches will help insulate the plant.