Hibiscus coccineus, commonly known as the scarlet rose mallow, Texas star hibiscus, brilliant hibiscus or swamp hibiscus, is a vigorous, woody-based perennial that typically grows 3-6 feet tall. It is native to marshes and swamps in Alabama, Georgia, Virginia and Florida, but it can be grown in gardens across the United States.
Despite its common name Texas star, the plant is not found naturally in Texas. In addition to the scarlet-flowering variety, a white-flowering variety is also known as the white Texas star or lone star hibiscus.
The Texas Star hibiscus (Hibiscus coccineus) grows in U.S. Department of Agriculture plant hardiness zones 5 through 10, although it may die back to the ground each fall in zones 5 through 8. This shrub can reach up to 8 feet tall in areas where they don’t experience winter dieback, but in colder regions or with pruning, they grow to only about 4 feet high.
This plant has hollyhock-like, 5-petaled, bright scarlet red flowers that bloom in the upper leaf axils over a long mid-summer to early fall period. Each flower is 3-5 inches in diameter with a prominent center staminal column.
The leaves of Hibiscus coccineus are deep green and measure 5-6 inches long, providing a lush, tropical backdrop to the vibrant flowers. The plant is hardy and can grow in full sun to part shade, preferring moist to wet soil conditions. It can be grown in containers in colder regions, where it can be moved indoors during winter.
Hibiscus coccineus attracts butterflies and hummingbirds. It can be used to make a wildlife-friendly garden. It can be used as a specimen plant in the landscape or as part of a mixed border or courtyard. It’s also a good choice for planting around a pond or in the shallow parts of a stream. With proper care, a Texas Star hibiscus thrives year after year.
Propagation of Hibiscus coccineus is relatively easy. It can be grown from seed, either harvested from the plant or purchased from a nursery. The seeds should be sown in early spring after the risk of frost has passed. Alternatively, you can take 5-6 inch long stem cuttings in spring, dip them in rooting hormone, and press them 3 inches into a container filled with peat moss. Keep the cuttings moist and out of direct sunlight until new leaves appear, then transplant them to their permanent position.
Hibiscus coccineus requires annual cutting back to encourage new growth and promote flowering. You can also apply a mulch of dry vegetation on the soil surface in winter to keep the soil warm.
How To Care for Hibiscus coccineus
- Grow the plant in a well-drained, full-sun planting bed. In areas with high rainfall, select a slightly sandy planting location to encourage good drainage.
- Spread a 2- to 3-inch layer of mulch over the bed to retain moisure and keep down weeds. Replenish the mulch to maintain its depth in fall and spring.
- Fertilize once a month during the spring and summer when the plant is actively growing. Apply a balanced fertilizer blend at the lowest monthly rate recommended on the package label.
- Water hibiscus shrubs weekly so the soil remains moist throughout the root zone, supplying approximately 1 to 3 inches of moisture a week. Hibiscus may require more frequent watering during dry periods.
- Inspect the undersides of hibiscus leaves periodically for aphids, the primary pest of the plant. Rinse the insects from the foliage if they are present. For severe aphid infestations, water the hibiscus thoroughly. Wait two hours then apply an insecticide that is labeled as safe for hibiscus plants.
- Cut back the hibiscus to the ground in early winter if cold weather kills back the stems. Increase the mulch level to 5 inches to protect the crown of the plant. The hibiscus sends up new growth in spring. Cut back the plant by up to half its height in late winter if cold doesn’t kill back the plant but you want to control its size.