Rose of Sharon is not a rose at all. It is a member of the Hibiscus family, and it looks just as tropical as its cousins. With large delicate flowers sprouting all over it in the summer, it is a lovely plant. Some varieties are even hardy through zones 4 to 9 although most can only stand the winter in zone 5. While warmer climates need not worry, zones 4 to 6 should winterize Rose of Sharon to give it proper winter protection.
Water Rose of Sharon normally throughout the fall. Water it at least once a week for 5 minutes a watering if the weather is dry. Rose of Sharon needs the water to get through the winter.
Deadhead any remaining flowers at the base of the Rose of Sharon. As the weather cools, the leaves of Rose of Sharon will turn yellow and drop. This is normal. Remove the leaves from the plant if you wish. You can also allow them to fall naturally.
Stop watering Rose of Sharon when the ground freezes in the winter. You need not water Rose of Sharon again until the ground thaws.
Mulch around the base of the Rose of Sharon. Place leaves, straw or pine needle mulch all around the base of the Rose of Sharon to a height of 2 to 3 feet and with a diameter of about 4 feet. Mulch after the ground has frozen.
Cover your Rose of Sharon in a burlap sack or a clear plastic bag once the weather drops below freezing. The clear plastic bag will offer more wind protection. Leave the bag or sack over the Rose of Sharon until the weather warms to at least 50 degrees Fahrenheit and there is no wind.