Hardy Hibiscus

Hardy Hibiscus (Hibiscus moscheutos)

Swamp Rose Mallow, Rose Mallow

Full sun, wet to moderately wet moisture level, organically rich soil, strongly acid to neutral pH.

4–8 feet tall; blooms summer into fall with dinner-plate-sized flowers (8–10 inches in diameter) in red, pink, white, or bicolor with a crimson center; spreads slowly by seed.

Germination Code: C(60) — nick or soak seed 24 hours before sowing; easy to grow from seed. Does not transplant well once established; select a permanent site.

Native region: Statewide in Tennessee, absent only from the southwest corner of the state; native to wetlands, pond margins, and low woods.

Hardy hibiscus is native to the wet sites common throughout Middle Tennessee and performs exceptionally well in the poorly drained clay low spots where most perennials rot. Plants die to the ground with frost and re-emerge very late in spring — often not until late May in Columbia — which can mislead gardeners into thinking they have died; mark locations clearly to avoid accidental disturbance. The massive flowers last only one day each but new buds open continuously from July through frost. Japanese beetles are a serious and reliable pest, often skeletonizing leaves; plan for control or accept significant foliar damage in years of high beetle pressure. May need staking on exposed sites.