Can You Divide Hardy Hibiscus Plants & How?

Hardy hibiscus flowers measure up to 12 inches in diameter.

Hardy hibiscus is a colloquial name used for swamp mallow (Hibiscus moscheutos), which grows as a herbaceous perennial in U.S. Department of Agriculture hardiness zones 5 through 10. Gardeners know of famous cultivars of it, such as Lord Baltimore and Lady Baltimore.

Time Frame

Dig up and divide root clumps of hardy hibiscus in either spring or fall. In cold winter regions, do this in spring just before new growth sprouts. In chilly, milder winter regions spring or fall is OK, but wait until fall frost kills the flowers and stems.

Significance

Naturally forming a nice clump, hardy hibiscus doesn't require scheduled digging and dividing in the garden to maintain a healthy, flowering plant. Large root clumps can be sliced into halves or natural smaller root clusters and replanted to expand the collection.

Care

Plant root divisions of hardy hibiscus back into the soil at the same depth they previously grew. Keep the soil moist to help re-establish roots. Mulch the soil with compost to enrich the soil's fertility. If planted in fall, do not let the soil dry out or the root ball will heave in the freezing and thawing temperatures.

References

• North Carolina State University: Hibiscus moscheutos
• "The Perennial Care Manual"; Nancy J. Ondra and Rob Cardillo; 2009

Resources

• National Gardening Association: USDA Hardiness Zone Finder
• Floridata: Hibiscus moschuetos