Hibiscus moscheutos, also known as perennial hibiscus or rose mallow, feature large, showy flowers that bloom from the middle to late summer, offering bold color and tropical appeal to the landscape in U.S. Department of Agriculture plant hardiness zones 5 through 10. They grow to heights of 5 to 8 feet, with a spread of 2 to 3 feet, depending on the variety. Propagation, a term that describes several plant reproduction techniques, allows gardeners to expand their gardens, growing more show-stopping hibiscus flowers. Gardeners can propagate perennial hibiscus in one of three main ways: seeds, cuttings and division.
Gather seeds once the flowers fade. Gardeners can pinch the seed head off and place it in a cool, dry location to dry the seeds; or, let the pods dry on the plant before breaking them open to collect the seeds. Store seeds in a cool, dry spot until you are ready to plant them.
Prepare the seeds by soaking them in warm water for one to 24 hours before planting. This breaks their dormancy, allowing the process of germination to begin. Use a sharp knife to lightly nick the seed on one edge. This allows maximum water penetration after planting.
Start seeds inside about 12 weeks before the last frost, transplanting seedlings after the danger of frost has passed. Place seeds 1/4 inch deep in a container or pot filled with potting mix. Place in a sunny, warm area. Keep the soil moist. Seeds take 14 to 30 days to start sprouting. Alternately, gardeners can sow seeds directly in the garden in fall or after the danger of frost has passed in spring. When sowing seeds or planting young hibiscus moscheutos plants outdoors, select a sunny planting area with nutrient-rich, well-draining soil.
Propagation from Cuttings
Select a 5- to 6-inch stem. Cuttings should be taken from new growth that is about as thick as a pencil. Place the cutting directly into a glass or container of water after cutting.
Remove any of the cutting's lower leaves before placing it in a container filled with 1 part peat and 3 parts sand. The cutting should begin forming roots within five weeks.
Transplant the cutting into a larger container or directly in the garden after its roots are formed.
Propagation by Division
Dig a trench around the plant’s drip line, severing roots. Use a shovel to place an angled cut down and under the plant. Repeat the angled cutting around the outer edge of the drip line until you can lift the plant up from its hole.
Separate the plant into three or four smaller plants by spreading the roots apart and pulling or cutting clumped areas apart. Remove any discolored or eroded roots.
Plant the newly divided hibiscus moscheutos in holes that are as deep as the roots and wide, or wider than the spread of the roots. Cover with nutrient-rich soil and keep evenly moist.
Things You Will Need
- Collection/storage container
- Sharp knife
- Container (optional)
- Potting mix (optional)
- Sharp shears
- Container/flower pot
- Divide perennial hibiscus plants on a cloudy spring day since cool, cloudy weather offers less stress for the plant than sunny days during the growing season.
- After dividing plants, keep roots cool and moist before replanting.
- National Junior Horticultural Association: Plant Propagation
- Learn 2 Grow: Hibiscus Moscheutos
- Clemson Cooperative Extension: Hibiscus
- The New Sunset Western Garden Book; Editors of Sunset Magazine
- University of Minnesota Sustainable Urban Landscape Information Series: Dividing Perennials
- Jupiterimages/Photos.com/Getty Images