By Julie Christensen
The genus Hibiscus (Hibiscus spp.) includes more than 200 species of perennials, annuals and shrubs. When you think of hibiscus, you might think of the exotic, tropical plants that are hardy only in USDA plant hardiness zones 8 through 11, but there are many other types of hibiscus. Most of them are easy-to-grow, long-lived plants.
Varieties and Types of Hibiscus
Related to okra, hollyhocks and cotton, the hibiscus family includes the Confederate rose (Hibiscus mutabilis), an old-fashioned favorite in the South that grows 8 to 10 feet tall and produces large, multi-petaled blooms that change from white to pink to red. It is hardy in USDA zones 7 to 9.
Rose of Sharon (Hibiscus syriacus) grows in zones 5 through 9, making it a suitable choice for most gardens in the U.S. Rose of Sharon is a vase-shaped shrub that grows 6 to 10 feet tall. It produces large, papery blooms in a variety of colors. Rose of Sharon blooms from mid-to-late summer, when most other flowering shrubs have lost their blooms.
Common rose mallow (Hibiscus moscheutos) grows in USDA zones 5 through 10 and is often found near swamps and marshy areas. It grows 8 feet tall and has large blooms in white, pink or red.
Chinese hibiscus (Hibiscus rosa-sinensis) is hardy only in USDA zones 9 through 11. This shrub has large, exotic flowers that come in a variety of shades, including hot pink, yellow, orange, purple, white and red. Chinese hibiscus is often grown as an annual plant in the North, or brought indoors during the winter and treated as a houseplant.
Another tropical plant treated as an annual in the U.S. is red-leaf hibiscus (Hibiscus acetosella). This plant has gorgeous reddish foliage that resemble maple leaves.
Most hibiscus plants are grown from potted nursery plants. You can also take green wood cuttings for shrub hibiscus or start annual hibiscus from seeds sown indoors 6 weeks before the last frost. Confederate rose is often called a pass-along plant because it’s easy to share through cuttings or divisions.
Regardless of the species, all hibiscus plants grow best in full sun. They need fertile, well-draining soil that stays moist, but not soggy. In most cases, you’ll only need to amend the soil with a bit of compost to improve drainage, but amend heavy clay soils with peat moss and additional compost or grow hibiscus in a raised bed.
Fertilize hibiscus plants every spring with ¼ cup 10-10-10 fertilizer. Established plants can be mulched with 3 to 4 inches of wood chip mulch to conserve moisture and prevent weed growth.
In some areas of the south, Confederate roses and other perennial hibiscus die back to the ground in the winter, eliminating the need for pruning. In more temperate climates, though, deadhead the blossoms before they go to seed. In the spring, prune the plants to remove dead and diseased limbs, old canes and branches that rub against each other. Another option is to prune back the entire plant by one-third after blooming. Don’t prune shrubs in early fall, though. Pruning stimulates new growth, which is more likely to be damaged by winter temperatures.
Hibiscus Pests and Diseases
You’re unlikely to run into many disease problems in temperate climates, but fungal leaf spots can be a problem in warm, humid areas. Remove the infected leaves promptly and clean up any debris on the ground. Use soaker hoses instead of overhead sprinklers and space the shrubs so air circulates freely.
Aphids, whiteflies and Japanese beetles can infest hibiscus, although damage is usually minor. Spray both sides of the leaves with insecticidal soap or oil to combat aphids and whiteflies. To manage Japanese beetles, handpick them and drop them in soapy water or use a pesticide labeled for treating Japanese beetles. Baits designed for Japanese beetles are largely ineffective, according to studies at the University of Kentucky, and can actually cause more damage by encouraging Japanese beetles in large numbers.
Common Questions and Answers About Hibiscus
by Erin Marissa Russell
Are hibiscus easy to grow?
As long as they get six hours of sun per day, the soil they are planted in is well-draining, and you provide them with enough water, hibiscus are easy to grow.
Are hibiscus roots invasive?
Hibiscus plants do not have invasive roots. On the contrary, their root systems are shallow and make the plants prone to blowing over in strong winds.
Can you grow hibiscus in pots?
Yes, hibiscus plants grow well in containers. Use a lightweight potting mix with good drainage, such as one with compost and perlite or vermiculite. Give the plant about two weeks of shade to soften its transition, then find a spot to place the container where the hibiscus will get at least six hours of sun per day. Check the plant regularly to see if it needs water, as hibiscus growing in a container may need watering twice a day when the weather is warm. Feed your hibiscus with a water-soluble fertilizer made especially for hibiscus plants, and follow the instructions from the manufacturer.
Can you plant hibiscus in the ground?
Yes, hibiscus plants can grow directly in the ground. Choose a location with well-draining soil where your plants will get at least six hours of sunlight per day. Bury the hibiscus to the same level it was in its container for best results.
Do hibiscus plants come back every year?
Tropical hibiscus will die once exposed to temperatures of 20 degrees Fahrenheit or lower and will not come back the following year. However, hardy hibiscus plants can be cut back to a few inches from the ground and will grow back from the roots when grown in USDA hardiness zones 4 to 9.
Do you deadhead hibiscus?
Deadheading your hibiscus allows it to replace the dead flowers with fresh blooms all season long as well as making the plant visually neater and more attractive. Once a blossom has faded, just pinch it off below the base of the flower.
How big will a hibiscus get?
In the right climate (areas that do not get frost), hibiscus plants can grow up to 15 feet tall.
How do I keep my hibiscus blooming?
There are several ways to encourage your hibiscus to bloom all season long. One is to deadhead your plant by removing spent blooms, pinching them off below the flower base. Provide your hibiscus with plenty of water. In warm seasons, you may need to water it twice a day. For lots of blooms, keep your hibiscus somewhere where temperatures stay between 65 and 95 degrees Fahrenheit. Feed with a balanced water soluble or slow release fertilizer, such as a 10-10-10 or 20-20-20 blend.
How do you collect seeds from a hibiscus?
If hibiscus flowers are pollinated, they will produce seed pods after flowers drop off the plant. Keep an eye on the plant after flowers have fallen to watch for the seed pods to develop. Leave the green pods on the plant until they start to turn brown and crunchy. Then collect them quickly, before they open and let out the seeds. Save the seeds somewhere they will stay safe and dry, such in a loosely closed paper bag or in a box.
How long do hibiscus plants live?
Older varieties of hibiscus can live for 50 years or longer when cared for properly. New hybrids of hibiscus have lifespans of five to 10 years.
How long does hibiscus take to grow?
Tropical hibiscus reach their mature height of seven to 12 feet tall in two or three years.
How much sun does a hibiscus plant need?
Hibiscus plants require full sun, which means they need at least six hours of sunlight per day to thrive. However, newly planted hibiscus in containers should spend their first two weeks in a shaded area before being moved to a sunnier spot.
How often should hibiscus be watered?
Hibiscus plants are known for liking lots of water, and depending on your climate, your hibiscus will need to be watered once or twice a day. Give hibiscus plants one or two inches of water per week, and make sure the soil they are planted in is well-draining. If the leaves at the top of the plant are yellowing or the plant is dropping leaves, it may not be getting enough water. If leaves are yellowing at the bottom of the plant or in the middle, it may be getting too much water.
Is the hibiscus an annual or a perennial?
Tropical hibiscus varieties must be brought indoors during winter, or they will grow as annuals. Hardy hibiscus are perennial, but they will die down to the ground and come back from the roots except for in the warmest growing zones.
Should I mist my hibiscus?
Hibiscus plants do not need to be misted. They do need plenty of water to thrive, and in hot weather, may need to be watered twice a day.
Should I remove yellow leaves from hibiscus?
If you want to trim yellow leaves from your hibiscus plant to make it more visually appealing, you can do so with sterilized shears. Yellow leaves at the top of the plant may occur when it needs more water. Yellow leaves at the bottom or middle of the plant can mean the hibiscus has received too much water. Nutritional deficiency can make leaves turn partially yellow and remain attached to the plant. Too much sunlight can cause yellow leaves or white spots on leaves. Yellow leaves can also indicate stress or infestation by spider mites.
What is a good fertilizer for hibiscus?
To feed hibiscus plants, you can use either a balanced slow release or water soluble fertilizer, such as 20-20-20 or 10-10-10.
What month do you prune hibiscus?
Prune your hibiscus plants in the spring, or do light pruning in the late summer and early fall. Do not prune hibiscus plants in late fall or winter.
What soil does hibiscus like?
Hibiscus plants prefer moist soil that drains well, with loamy and sandy soils being the best options.
Where is the best place to plant hibiscus?
Hibiscus should be planted either directly into the soil or in a container in a location where they will get at least six hours of sun per day and the soil is well-draining.
Want to learn more about growing Hibiscus?
Hibiscus from the National Gardening Association
Hibiscus from Clemson University
YouTube shows you how to prune tropical hibiscus.
Salisbury Greenhouse shows you about basic hibiscus care on YouTube.
National Gardening Association covers Hibiscus Plant Care
Julie Christensen learned about gardening on her grandfather’s farm and mother’s vegetable garden in southern Idaho. Today, she lives and gardens on the high plains of Colorado. When she’s not digging in the dirt, Julie writes about food, education, parenting and gardening.