Hibiscus vines come in many varieties, but only hardy hibiscus can withstand the winter temperatures throughout most of the United States. Like the tropical hibiscus, hardy hibiscus has large, showy flowers that can grow up to 12 inches across. Hardy hibiscus grows quickly in the landscape and some vines can reach heights of 15 feet tall with a spread of 8 feet. Hardy hibiscus are generally hardy to U.S. Department of Agricultural Plant Hardiness Zones 5 to 10.
Plant the hibiscus vine in a well-drained, sunny location in your garden. Dig a hole as deep as the root ball and two times as wide. Place the hardy hibiscus into the hole and cover it with soil.
Add 1 to 2 inches of water to the hibiscus vine a week. Hibiscus are from naturally humid climates and need plenty of water.
Apply 1 tbsp. of 10-5-5 fertilizer to the hibiscus vine in the late spring or early summer as the buds are forming. Add 1 tbsp. 5-10-5 fertilizer to the hibiscus once a month after flowering begins until September.
Cut back the hardy hibiscus vine to 1 foot when it reaches 2 feet tall. This will help the plant to generate more flowers.
Trim the hardy hibiscus vine to the ground after it dies back in the late fall or early winter.