Among the showiest flowering plants in Southern gardens, hibiscus typically bear funnel-shaped blossomssometimes as big as dinner plates and often with prominent stamens. The many species offer an astonishing range of flower colors, and most bloom over a long season. Flowers attract butterflies and hummingbirds. Whiteflies and aphids are common pests; insecticidal soap is a good control for both.
H. acetosella (H. eetveldeanus). REDLEAF HIBISCUS. Evergreen shrubby perennial. Zones TS; USDA 10-11; or grow in pots. From central and eastern Africa. Reaches 5 ft. tall and 3 ft. wide. Cultivated more for its foliage than its dark-centered red or yellow flowers. Leaves are up to 1 ft. across; they may be lobed (somewhat like a maple leaf) or unlobed. Color varies from green to deep purplish red. 'Haight Ashbury' leaves are heavily splashed with pink. 'Red Shield' has deep red foliage.
H. coccineus. TEXAS STAR. Shrubby perennial. Zones US, MS, LS, CS, TS; USDA 6-11. Native to coastal swamps of Florida and Georgia. Moderately fast-growing bush to 6 ft. tall and 3 ft. wide, with handsome glossy foliage; very showy scarlet flowers, 3 in. wide, bloom from June to October. Palmate leaves with three to seven lobes look much like those of Japanese maple (Acer palmatum). Use as an accent or at the back of a perennial border. Does well in either wet or well-drained soil. 'Lone Star' has blooms of pure white.
H. militaris. HALBERD-LEAFED ROSE-MALLOW. Shrubby perennial. Zones US, MS, LS, CS, TS; USDA 6-11. Native to marshes and wet woods from Pennsylvania to Minnesota, south to Florida and Texas. If grown in moist soil, quickly attains 8 ft. tall, 3 ft. wide. Dagger-shaped dark green leaves to 6 in. long; pinkish white, 4- to 6-in. flowers from May to October. Tolerates partial shade; takes heavy soils with poor drainage.
H. moscheutos. HARDY HIBISCUS, COMMON ROSE- MALLOW. Perennial. Zones US, MS, LS, CS, TS; USDA 6-11. Native to the southern U.S., and an old Southern favorite. Largest flowers of all hibiscus, some to 1 ft. across, on a plant 68 ft. tall and 3 ft. wide. Bloom starts in June, continues until fall. Oval, toothed leaves to 8 in. long are deep green above, whitish beneath. Plants die down in winter. Feed at 6- to 8-week intervals during growing season. Protect from wind.
Seed-grown strains often flower the first year if sown indoors and planted out early; these plants are bushier and more uniform than the species. Southern Belle strain grows 4 ft. tall; Cordials series plants are 3 ft. tall; Vintage series reach 23 ft. tall; Disco Belle, Frisbee, Luna, and Rio Carnival strains are 2212 ft. tall. Flowers are 812 in. wide, come in red, pink, rose, or white, often with a red eye.
The many cutting-grown selections and hybrids include the following. Unless otherwise noted, all reach about 4 ft. high.
'Anne Arundel'. Blooms to 9 in. across, in clear pink with a red eye.
'Blue River II'. Pure white flowers to 10 in. across. Foliage may have a bluish cast.
'Cranberry Crush'. Heavy producer of 7- to 8-in.-wide, cranberry-red to deep scarlet flowers that appear along the length of the stems. Foliage is deep green with purple overtones.
'Fantasia'. To 23 ft. high, with rosy pink, 9-in. flowers with a rosy red center.
'Fireball'. To 4 ft. tall, with 10-in., bright red flowers.
'George Riegel'. Pink, ruffly, 10-in. blooms with a red eye.
'Lady Baltimore'. Glowing pink, 6- to 8-in.-wide flowers with a large red center.
'Lord Baltimore'. Deep red, 10-in. blossoms over an exceptionally long period.
'Raspberry Rose'. Large plant, to 7 ft. tall and 10 ft. wide, with a profusion of bright raspberry-red blooms to 10 in. across.
'Royal Gems'. Grows 34 ft. tall, with bright pink flowers to 12 in. across. Oval, pointed, incurving leaves are an attractive dusky purple. Cold hardy.
'Summer Storm'. Light pink blooms with a red eye can reach 10 in. across. Grows 5 ft. tall and a little wider. Foliage is deep purple to chocolate-brown, striking in contrast to the flowers.
'The Clown'. Light pink flowers with red eye; 68 in. across.
'Turn of the Century'. Red-centered blooms with bicolor petals of pink and white range from 510 in. wide.
H. mutabilis. CONFEDERATE ROSE. Deciduous shrub. Zones LS, CS, TS; USDA 8-11. From China. Shrubby or treelike in the Coastal and Tropical South, 15 ft. tall, 8 ft. wide; acts more like a perennial in the Lower South, growing flowering branches from woody base or short trunk. Broad, oval leaves have three to five lobes. In late summer and fall, flowers open from buds that resemble cotton bolls. Blooms are 46 in. wide, opening white or pink often and changing to deep red by the next day. 'Rubrum' has red flowers. 'Flore Pleno' has double, rosy pink flowers.
H. rosa-sinensis. CHINESE HIBISCUS, TROPICAL HIBISCUS. Evergreen shrub. Zones CS, TS; USDA 9-11; provide overhead protection where winter lows frequently drop below 30F. Where temperatures go much lower, grow in containers and shelter indoors over winter; or grow as annual, setting out fresh plants each spring. Also makes a good houseplant that can be brought outdoors during the warm season.
A longtime favorite of Southern gardeners, this is one of the showiest flowering shrubs. Reaches 30 ft. tall and 1520 ft. wide in its native tropical Asia, but seldom grows over 15 ft. tall in the U.S. Glossy foliage varies somewhat in size and texture, depending on selection. Growth habit may be dense and dwarfish or loose and open. Flowers are single or double, 48 in. wide. Colors range from white through pink to red, from yellow and apricot to orange. Individual flowers usually last only a day or two, but the plant blooms continuously in spring and fall; may slow in summer, as high temperatures can cause bud drop. Aphids may also cause bud drop; use horticultural oil or insecticidal soap to control them.
Requires acid soil and excellent drainage; if necessary, improve soil or set plants in raised beds or containers. Fertilize monthly (potted plants twice monthly) with a general-purpose liquid fertilizer April to September, then stop fertilizing and let growth harden. For good branch structure, prune poorly shaped young plants when you set them out in spring. To keep a mature plant growing vigorously, prune out about a third of old wood in early spring. Pinching out tips of stems in spring and summer increases flower production. These are some of the selections available:
'All Aglow'. Tall (10- to 15-ft.) plant has large single flowers with broad, gold-blotched orange petals, pink halo around a white throat.
'Baja Breeze'. Compact and symmetrical at 23 ft. high and wide; good in large containers. Rich red flowers with darker red center.
'Bridal Veil'. Large, pure white, single flowers last 3 or 4 days. Grows 1015 ft. tall.
'Bride'. Very large, single, palest blush to white flowers. Slow to moderate growth to open-branched 4 ft.
'Brilliant' ('San Diego Red'). Bright red single flowers in profusion. Tall, vigorous, compact, to 15 ft. Hardy.
'Butterfly'. Small, single, bright yellow flowers. Slow, upright growth to 7 ft.
'Cajun Blue'. Pale lavender-gray flowers with a white eye. Open grower to 46 ft. tall.
'Chiffon Breeze'. Pale yellow flowers with a white eye. Grows 23 ft. high and wide; elegant choice for containers.
'Cool Wind'. White to softest pink flowers with a bright red eye. Compact grower, reaching just 23 ft. high and wide.
'Crown of Bohemia'. Double gold flowers; petals fade to carmine-orange toward base. Moderate or fast growth to 5 ft. Bushy, upright. Hardy.
'Diamond Head'. Large, double flowers in deepest red (nearly black-red). Compact growth to 5 ft.
'Ecstasy'. Large, bright red, single flowers with striking white variegation. Upright growth to 4 ft.
'Fiesta'. Large, single flowers in bright orange centered with a red-edged white eye; petal edges are ruffled. Strong, erect growth to 67 ft.
'Full Moon' ('Mrs. James E. Hendry'). Double, pure yellow flowers. Moderately vigorous growth to a compact 6 ft.
'Golden Dust'. Bright orange, single flowers with yellow-orange centers. Compact, thick-foliaged plant to 4 ft. tall.
'Hula Girl'. Large, single flowers in canary yellow with a deep red eye. Compact growth to 6 ft. Flowers stay open several days.
'Itsy Bitsy Peach', 'Itsy Bitsy Pink', and 'Itsy Bitsy Red'. Tall (10- to 15-ft.) plants with small leaves and small single flowers.
'Kate Sessions'. Large single flowers with broad petals; red with a gold tinge on petal undersides. Moderate growth to 10 ft. tall. Upright and open habit.
'Kona'. Ruffled, double pink flowers. Vigorous, upright, bushy growth to 1520 ft. Prune regularly. 'Kona Improved' produces fuller flowers in a richer pink.
'Kona Princess'. Small, double pink flowers on a 6- to 7-ft. shrub.
'Morning Glory'. Single, blush-pink flowers changing to warmer pink with white petal tips. Grows 810 ft. tall.
'Moy Grande'. Compact grower to 5 ft. tall. Single, brilliant rosy red flowers are huge, to more than 1 ft. across.
'Peppermint Flare'. Grows 4 ft. tall and wide. Blooms to 10 in. across are white to palest pink, with a red eye and pronounced red flecks.
'Powder Puff'. Double flowers of creamy white; during cool weather, take on a pink tinge. Grows 810 ft. tall.
'President'. Large single blossoms, intense red shading to deep pink in throat. Upright, compact, 67 ft. tall.
'Red Dragon' ('Celia'). Small to medium, double, dark red flowers. Upright, compact, 68 ft. tall.
'Reggae Breeze'. Golden blooms centered with a pink starburst and burgundy throat. At 23 ft. high and wide, a good choice for large pots.
'Ross Estey'. Heavy-textured, very large single blooms with broad, overlapping petals of pink shading to coral-orange toward tips; last 2 or 3 days on bush. Vigorous. To 8 ft. Very large, ruffled leaves in polished dark green.
'The Path'. Large, ruffled, single flowers in bright yellow shading to orange and bright fuchsia-pink in the center. Grows 68 ft. high.
'Vulcan'. Yellow buds open to large single flowers in red with yellow on the petal backs. Blossoms often last for more than a day. Compact grower to 46 ft. high.
'White Wings'. Profuse, narrow-petaled, single white flowers with small red eye. Vigorous, open, upright to 20 ft.; prune to control legginess. A compact form with smaller flowers is available.
H. schizopetalus. FRINGED HIBISCUS, CORAL HIBISCUS. Evergreen shrub in Zone TS; USDA 10-11; annual elsewhere. From tropical east Africa. To 915 ft. tall, 612 ft. wide, with weeping habit. Blooms almost all year, bearing white, pink, red, or yellow blossoms with fringed petals and an unusually long column of stamens that resembles a bottlebrush. Plants are sometimes kept small and grown in hanging baskets.
H. syriacus. ROSE OF SHARON, SHRUB ALTHAEA. Deciduous shrub or small tree. Zones US, MS, LS, CS, TS; USDA 6-11. This old Southern favorite has come full circle. Native to Korea and India (not Syria, despite the name), it was one of Grandma's standby plants for colorful summer blooms. But most nurseries sold unnamed seedlings only by color. When showier trees like crepe myrtle gained favor, rose of Sharon fell by the wayside. Improved, named selections now offer better blooms over a longer period, more colors, fewer seeds, and nicer forms.
Plant grows upright and compact when young, spreading and opening with age to 1012 ft. tall and 6 ft. wide; easily trained to a single trunk or espaliered against a wall. Leaves to 4 in. long, with three coarsely toothed lobes, emerge somewhat late in spring and drop in fall with little color. Flowers resembling those of hollyhock (Alcea) appear in summer. Blossoms are single, semidouble, or double, 2123 in. across, often with a contrasting purplish throat. Though single forms are more attractive than doubles, most produce more seeds (and hence, more seedlings) than doubles. Self-sown seedlings can be weedy. New sterile selections are seedless.
Easy to grow in almost any well-drained soil. Tolerates heat and drought. Prune in winter, as blooms form on new growth. Japanese beetles that eat flowers and leaves can be serious pests. Control by hand-picking the beetles or spraying plant with neem oil, a natural pesticide. Deer resistant.
Recommended selections include the following:
'Ardens'. Double lilac-purple flowers with darker center. Few seeds.
'Blue Bird'. Single, blue flowers with small red eye. Considered the best blue form for many years, this selection has now been surpassed by newer introductions.
'Blushing Bride'. Double, bright pink blossoms. Few seeds.
'Boule de Feu'. Double, deep violet-pink flowers. Few seeds.
'Freedom'. Double flowers in deep mauve-pink. Larger flowers than most doubles. Strong grower with handsome foliage. Few seeds.
'Jeanne d'Arc'. Double flowers of pure white. Few seeds.
'Pink Giant'. Large rose-pink blooms with a red eye and yellow stamens.
'Red Heart'. Single white flowers with a red eye. Strong grower.
Plants in the Chiffon series have soft-colored flowers with a ruffled center that gives them the look of anemones. Satin series plants are robust growers with blooms in rich shades of blue, light pink, rose-pink, and violet, all with a dark red center.
The U.S. National Arboretum has introduced selections developed by famed plant breeder Don Egolf. These plants are triploids; the extra set of chromosomes results in large blossoms with strong, heavy-textured petals. Because plants produce little seed, flowers appear over a long period. Choices include 'Aphrodite', bearing single, rose-pink flowers with a deep red eye; 'Diana' (the most popular of this group), with single, pure white blossoms; 'Helene', single, white flowers with a deep red eye; 'Minerva', single, ruffled, lavender blooms with a reddish purple eye.