Propagating a Native Hibiscus
Native hibiscus (Hibiscus spp.) plants give a tropical touch even to gardens in temperate climates. Bold, showy flowers are typical of these species, making them effective additions to butterfly and hummingbird gardens. Increasing your native hibiscus plants can multiply their beauty throughout your garden if you propagate them by collecting their seeds or taking stem cuttings.
Hibiscus plants include more than 300 species, many of which are not native to the United States. Some species, such as Hibiscus rosa-sinensis, are popular nursery plants but are native to tropical jungles in Asia and cannot survive as perennials in areas with freezing temperatures. Other species, such as swamp hibiscus (H. coccineus) and rose mallow (H. moscheutos) are native American plants that are reliably hardy in U.S. Department of Agriculture plant hardiness zones 6 through 9 and 5 through 10, respectively.
Native hibiscus plants propagate naturally in the wild by means of sexual reproduction. Because most hibiscus flowers are open for only one day, they maximize that small window of reproduction opportunity by producing large, showy blossoms that beckon pollinators to help fertilize them. After flowers are successfully fertilized, small, green seedpods form and grow as the seeds inside them mature. You’ll notice these seedpods after the flowers fall, but the seedpods must mature fully on the plant and turn brown before the seeds are ready to harvest.
Propagation by Seeds
When the seedpods start to crack open slightly, which usually happens in late summer to autumn, it’s time for you to remove them. If you leave them on the plants, the seeds will naturally fall to the soil, where they may germinate and grow the following season. Birds and other predators may eat these seeds, and the seeds may experience sporadic germination, depending on their location. If you collect the seeds and sow them indoors in containers the following spring, then small seedling plants will be ready to set outside after all danger of frost passes. A soil-less potting mix for starting seeds is suitable. Seeds germinate best in darkness. So sow them at a depth at which they can be covered lightly with the potting mix, and keep the potting mix moist but not soggy.
Propagation by Cuttings
Imitating nature’s natural propagation methods, you can produce larger hibiscus plants sooner by using stem cuttings instead of sowing seeds. When stems break and fall on moist ground in the wild, they often root readily. Similarly, you can cut sections of stems and press the cut ends into the ground, or into soil in containers. If you keep the growing mix moist and the cuttings sheltered from direct sunlight, the cuttings will grow roots. The rooting success increases if you take pencil-size, 6-inch long cuttings from stems in spring when new growth flushes.
Propagation by Stems
You also can propagate new plants from stems that you leave on hibiscus plants. If you choose long stems that are close to ground level, you can bend each of them down gently and secure each with a brick so that the stems maintain contact with the soil. So that you don't injure the stems, dig a shallow trench to place each stem in, and cover the stems with soil before you hold down each stem with a brick. When roots form, you can remove the bricks and clip the rooted stems below the roots for planting in another location.
Victoria Lee Blackstone is a horticulturist and a professional writer who has authored research-based scientific/technical papers, horticultural articles, and magazine and newspaper articles. After studying botany and microbiology at Clemson University, Blackstone was hired as a University of Georgia Master Gardener Coordinator. She is also a former mortgage acquisition specialist for Freddie Mac in Atlanta, GA.