Should You Cut Back a Sub Zero Hibiscus?

Cutting Back in the Fall

• When the plant has completed flowering in fall and is looking tattered or has been hit by frost, cut all the branches down nearly to the ground. It is a good idea to leave stubs several inches above ground. The reason is that in the spring hibiscus are very late to leaf out and it will be helpful to see where the spot is that they grow so you do not try to plant other plants too close. If you leave the stems up over the winter, the seed heads will provide some decorative winter interest, but they may also create excessive unwanted re-seeding if the conditions are right.

Cutting Back in the Spring

• The only time to cut hibiscus back in the spring is if you did not cut it back in the fall. Do this early before the new growth has begun to grow. Cut it all the way to the ground.

Cutting Back in the Summer

• If you want to increase the number of branches and flowers and produce a slightly shorter plant (the plant will naturally grow as tall as five to seven feet tall), prune the branches to about half their height when they get about three feet tall. Depending on your climate, this will be sometime in mid-June to early-July. According to Tracy DiSabato-Aust, a well-known perennial expert, this treatment creates a fuller plant, may avoid some early Japanese beetle damage and delays flowering by about one to two weeks.

Additional Notes

• Hibiscus prefers locations with moist, rich soil. They do best in full sun, but can tolerate some partial shade. They flower from July through frost. Deadheading improves the appearance, but is not required for future blooming. They are long-lived plants and do not need division. Hibiscus are heavy feeders and should be fed in the spring with a granular fertilizer suitable for flowering plants.