Hibiscus moscheutos, commonly known as the rose mallow, swamp rose-mallow, eastern rose-mallow or crimsoneyed rosemallow is a cold-hardy perennial wetland plant that can grow in large colonies. It is native to the eastern United States, particularly in areas such as marshes, swamps, floodplains, river banks, moist meadows, and moist woods. From Texas to the Atlantic states, its territory extending northward to southern Ontario.
It is a member of the Malvaceae family. It grows to a height of 3-7 feet and has a spread of 2-4 feet. It features large, hollyhock-like flowers that can be up to 8 inches across. The petals are usually white, pink, or a combination of these colors, with a sharply contrasting dark eye. Each flower lasts for only 1-2 days, but new flowers open each day in rapid succession over a long July to September bloom period. At the peak of bloom, a large plant can produce 20 or more flowers per day.
Rose mallow grows best in U.S. Department of Agriculture plant hardiness zones 5 through 10. The leaves of Hibiscus moscheutos are broad and have toothed edges. They are green above and white-hairy beneath. The leaves can be lobeless or have 3-5 shallow lobes.
Hibiscus moscheutos cultivars include “Kopper King,” “Lord Baltimore” and “Disco Belle Pink.” “Kopper King” has coppery leaves with 12-inch-wide white or pink flowers with burgundy centers. “Lord Baltimore” and “Disco Belle Pink” have pink flowers with red centers and dark green leaves.
When growing in the landscape, it is a larval host for the common checkered skipper, the gray hairstreak, the Io moth, and the pearly wood nymph.
Hibiscus moscheutos can be grown from seed or stem cuttings. Seeds should be sown in early spring after the risk of frost has passed. Stem cuttings should be taken in spring, dipped in rooting hormone, and pressed 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 moscheutos is not only a beautiful ornamental plant but also has practical uses. The edible parts of the plant include its leaf buds and young leaves, flowers, immature seed pods (which can be prepared as okra), seeds, and roots. The plant has also been used externally to reduce swelling and pain from bruises and insect stings.
How to Care For Rose Mallow
- Water the hibiscus deeply once a week, and more often during periods of low rainfall. Never allow a hibiscus to dry out completely. Water the plant at ground level rather than from above to help prevent the spread of viral and fungal diseases such as rust, verticillium wilt and rot.
- Feed hibiscus with a time-release fertilizer every six to eight weeks during its active growing period from spring through fall. For the most lush flowering, supplement the time-release fertilizer with a weekly application of a water-soluble fertilizer, according to the directions on the label.
- Remove the flowers from the hibiscus as they fade. Like daylily flowers, blooms on the hibiscus last for only one day. Keeping the hibiscus deadheaded helps tidy the plant and also stimulates production of new flower buds.
- Cut the plant’s stems down to 3 to 6 inches in the fall, in climates up to USDA zone 9 that have freezing weather. If you garden in USDA zone 10 or above, only remove any dead or diseased stems, using sharp pruning shears, once the hibiscus begins sending out its spring growth.
How to Prune Rose Mallow
- Examine the base of last year’s mallow plant in midspring for new shoots emerging from the crown of the plant. The plant is often slow to start in spring. Gardeners sometimes remove the plant before it has a chance to sprout.
- Cut dead stems of last year’s rose mallow down to the ground with hand pruners. The plant dies all the way back each winter even in the mildest of climates.
- Pinch off faded flowers every few days to keep the shrub looking its best. The plant’s extravagant blooms each last only one day and then fold over, becoming unsightly mush.
- Remove seed heads as they develop to keep the plant blooming and to prevent reseeding. The plant can produce many volunteer seedlings, especially when it is in the moist soil it prefers.