Hibiscus is a genus of flowering plants in the mallow family, Malvaceae. The genus is very large, comprising several hundred species that are native to warm temperate, subtropical and tropical regions throughout the world. Also referred to as hardy hibiscus, rose of sharon, and tropical hibiscus, the plant boasts showy flowers in shades of orange, yellow, pink, red, and multicolor. Tropical hibiscus flowers typically grow 4-6 inches across. Rose of Sharon varieties produce smaller flowers, but reach up to 12 feet tall and 10 feet wide. Hardy in USDA zones 5-9, this plant thrives in full sunlight. Hibiscus plants are a great container plant on patios and near pool areas or along the back of flower beds.
Rose of Sharon plants are very easy to grow. Choose a location that will get full sunlight. Plant your Hibiscus in fertile, well-drained soil to produce a healthy plant. Species that die back each year should be spaced 2 to 3 feet apart. To prevent breakage of long stems, choose a planting site that is not exposed to strong winds. Hibiscus plants will also grow well in containers.
Hibiscus plants require moist well drained soil. Typically, this plant needs one inch of water per week. They like constantly moist, but not soggy soil. During the bloom time, they may need larger amounts of water. If a Hibiscus dries out too much, the foliage will drop and the plant will look like a mound of dead sticks. Despite needing a lot of water, be careful about too much sitting water as this can cause root rot.
A blooming Hibiscus plant needs a lot of nutrients. During the summer months, a fertilizer with high potassium is best. Use a diluted liquid fertilizer once a week or a slow release fertilizer once a month. Apply at the base of the plant, avoiding getting the foliage wet. Water well after application. Careful of over fertilizing, as too much phosphorus can kill the plant.
Hibiscus bloom on this year’s growth (new wood), so it is best to prune in the early spring. Pruning encourages more branching and more flower stalks. To promote reblooming, remove spent flowers before they form seed heads, by snipping back by one third. This also helps to keep the plant tidy. In the fall, you can prune the plant to shape it.
Caring For Hibiscus in Pots
Many gardeners prefer to plant Hibiscus in containers. For the best blooms, place the container in a location that will get at least six hours of sunlight each day. Hibiscus prefer a tight fit when planted in a container. When repotting, choose a slightly larger container allowing only a little room for growth. Plant the root ball one inch below the edge of the container. Surround the root ball with good quality potting mix. Make sure that the container has good drainage holes.
Winter Care for Hibiscus
Hibiscus plants grown in the garden will die back after the first hard frost. Cut the plant down 4-5 inches and wait for them to sprout back up in the spring. Container grown Hibiscus can overwinter indoors if provided with warm temperature and a lot of light. Indoor Hibiscus will need consistent moisture, but be careful not to allow the plant to sit in water. Winter is a resting period for the plant, so minimal watering and fertilizing is best.