Overview
Hibiscus includes both tender tropical species (like Hibiscus rosa-sinensis, which is hardy only to zone 9a) as well as hardy species and hybrids suitable for Wisconsin gardens. For a show-stopping plant when in bloom, the old reliable ‘Lord Baltimore’ hibiscus is hard to beat. This moderately tall plant with bold crimson flowers is an improved sterile hybrid that was introduced in 1955. It was hybridized by Robert Darby from several Hibiscus species native to wetlands of the eastern U.S., including H. coccineus, H. laevis, H. moscheutos, and H. palustris. It remains one of the best pure red flowered cultivars and is hardy in zones 5a to 9b.
This vigorous, somewhat shrubby herbaceous perennial grows 4 to 5 feet tall and 2 to 3 feet wide (or even bigger in some locations) and dies back to the ground in winter. The new shoots emerge very late in the spring (mid-June many times), but then grow quickly. The reddish brown stems are sturdy and erect and are almost woody at the base. Plants grown in a suitable site usually do not need staking. The glossy, medium green leaves are deeply lobed (an exaggerated maple shape), creating a relatively coarse texture, with burgundy petioles.
Plants flower profusely from mid-summer to early fall (about July through September). Each satiny flower is up to 10 inches across, with five ruffled petals that overlap slightly and a prominent central staminal column. Each flower only lasts a day, but one or more flowers usually open each day. The spent flowers will eventually fall to the ground but deadheading regularly improves the appearance of the plant.
Landscape Use of Hibiscus ‘Lord Baltimore’
‘Lord Baltimore’ makes a great specimen plant. It can be used at the back of a perennial border or as an airy screen or hedge. It’s a great accent plant when in bloom, but many people are not fond of the foliage. It combines well with other mid-to late-late summer bloomers, such as purple coneflower (Echinacea purpurea), black-eyed Susan (Rudbeckia spp.), sunflower, and ornamental grasses. Surround it with cannas and elephant ears for a tropical feel to your landscape.
Hardy hibiscus grows best in moist soils rich in organic matter, but is easily grown in most average to wet soils and therefore is quite useful in low spots and along streams or ponds. It also does well in clay soils. Regular deep watering is recommended in soils that are not naturally consistently moist.
It does best in full sun but will grow in light shade, although flowering will not be as strong. Stems are susceptible to breaking at ground level in severe winds, so consider planting in a protected site if you are in a windy location. Fertilize when growth begins and again in midseason. Cut the stems back to a few inches in late autumn (leaving enough to mark the location of the slow-emerging plants in spring). A winter mulch may help survival in colder zones.
Hardy hibiscus generally do not have any serious pest problems, although Japanese beetle can cause significant defoliation and deer like this plant in some places (but don’t always favor it).
Propagating Hibiscus
This cultivar and other vegetative cultivars are propagated vegetatively. Take stems cuttings in early fall. Some cultivars of H. moscheutos and unimproved hibiscus species can be grown from seed. Germinate the seed at warm (70 to 75 °F) temperatures and keep the media moist during germination.
Cultivars of Hibiscus
In addition to ‘Lord Baltimore’ there are many other spectacular cultivars of Hibiscus that are hardy to zones 4 or 5, as well as named selections of H. moscheutos. These are just a few of the many available:
- ‘Disco Belle’ series is a seed propagated semi-dwarf strain of H. moscheutos that grows 2 to 3 feet tall) with flowers in pale pink, dark pink, rose, red or white all with a red eye.
- ‘Blue River II’ has large, pure white flowers and blue-green foliage.
- ‘Galaxy’ is a seed strain that grows 4 feet tall, in a mix of white, pink, and red flowers, all with red eyes.
- HONEYMOON™ series is a compact, hybrid seed strain that grows 2 to 3 feet tall and about 2 feet wide. Available in Deep Red, White with Eye, Light Rose, and a Mix of these colors. Zone 5a hardy.
- ‘Lady Baltimore’ has pink flowers with red eyes.
- ‘Luna’ series is a seed propagated, compact F1 hybrid H. moscheutos series, available in white, blush, pink, rose, red, and pink swirl. Good performance in large containers.
- ‘Moy Grande’ features exceptionally large (to 12 inches across) rose-pink flowers in flushes of bloom through the summer. Deadheading promotes reblooming.
- SUMMERIFIC® ‘Glitter Bomb’ (PPAF) is a vegetative hybrid cultivar with large (7 inch diameter) flowers with irregular red patterning and eyes. Grows 4 to 4½ feet tall and 5½ to 6 feet wide. Zone 4a hardy.
- SUMMERIFIC® ‘Holy Grail’ (PP 31,478) combines very dark purple leaves with vivid, deep red flowers – a “holy grail” in hibiscus breeding. Grows 4 to 4½ feet tall and 4 to 4½ to 5 feet wide. Zone 4a hardy.
- ‘Turn of the Century’ has pinwheel striped flowers in dark red and light pink.
- ‘Watermelon Ruffles’ (PPAF) is early blooming, with magenta pink flowers with puckered, ruffled petals and bronzy green leaves. Grows 4½ feet tall and wide. Zone 4a hardy.
Author: Susan Mahr, University of Wisconsin-Madison
Reviewers: Allen R. Pyle, Horticulture Outreach Specialist, UW-Madison Extension, Bruce Spangenberg, Horticulture Outreach Specialist, UW-Madison Extension
Revised: October 2026
