Scarlet rose-mallow: complete guide

Hibiscus laevis, commonly called Scarlet rose-mallow, Halberd-leaf rose-mallow, or Military hibiscus, is an ornamental shrub from the mallow family (Malvaceae), native to wetland, swamp, and marshy habitats of southeastern Canada and eastern North America, from Florida to Texas, Minnesota, and throughout the Great Lakes region. The plant typically reaches 1 to 2 meters in height, developing a multi-stemmed, bushy growth habit with smooth, glabrous stems. The foliage is bright green with prominently lobed, halberd or spear-shaped leaves that provide interesting texture year-round. From July through September, the plant produces large, spectacular flowers typically 10 to 15 cm in diameter, colored pale pink to purple with a striking dark-red or crimson center. The flowers are visited eagerly by bees, butterflies, and hummingbirds. Hibiscus laevis requires full sun (minimum 6 hours direct insolation daily) and performs optimally in wet to very moist soils. The species is hardy to USDA zone 5 (-30 degrees C) and can tolerate even seasonal inundation. It is slow to leaf out in spring; new growth appears late (May-June in most temperate regions). The plant is very long-lived once established. Pruning in early spring removes dead wood and encourages branching and profuse flowering. Propagation is via seed (sow with warm-stratification) or spring division of mature clumps. In landscape design, Scarlet rose-mallow serves excellently as a background shrub in water gardens, along pond and stream margins, in rain garden and bioswale plantings, in wet woodland edges, and anywhere moisture-tolerant, late-summer color is desired. The spectacular blooms make it a focal point in any wetland garden.