Flowering shrubs are the hard-working heart of a garden. These cheerful stalwarts can be planted on either side of the front door; they frame the spaces of a patio; and they contribute form, texture, and structure to flowerbeds. In southern gardens especially, flowering shrubs bring color and grace to gardens over a long growing season. The best choices adapt gracefully to long, hot summers and do not need a chilly winter to encourage luxurious blooms.
Jimmy Turner, director of gardens at the Dallas Arboretum and Botanical Garden, recommends some modern cultivars of old-time favorites. Turner's top recommendations are tough, adaptable, and attractive plants: They bloom reliably without pampering, aren't bothered by pests, and will not outgrow their places in the garden.
"My new favorite flowering shrub is Double Take flowering quince (Chaenomeles spp.)", Turner says. "These quinces surprised the living daylights out of me." Double Take cultivars are compact, drought-tolerant, thornless, and vigorous spring bloomers. Their ruffled double flowers are up to 2-1/2 inches across; at first glance, the blooms look like a camellia or a rose. Double Take Pink Storm, Orange Storm, and Scarlet Storm are rounded, multistem shrubs; they grow to about 6 feet tall in light shade or full sun. Zones 4-8
Dwarf crape myrtles open up lots of new possibilities for southern gardeners: these compact shrubs are sized for mixed flowerbeds, and they also flourish in pots. Razzle Dazzle dwarf crape myrtles (Lagerstroemia) were developed by the renowned plantsman Michael Dirr. Like full-size crape myrtles, they bloom from summer into fall, and their showy flowers last for up to three months. Six cultivars (Berry Dazzle, Cherry Dazzle, Diamond Dazzle, Dazzle Me Pink, Strawberry Dazzle, and Sweetheart Dazzle) all grow to 3-4 feet tall in full sun. They are drought-tolerant and mildew-resistant. Cut them back to about 8 inches every other year, Turner suggests: they'll bounce right back. Zones 6-9 Learn more about crape myrtles.
The U.S. National Arboretum's shrub-breeding program in Tennessee has produced two promising new oakleaf hydrangeas (H. quercifolia): 'Ruby Slippers', and 'Munchkin'. They're destined for the big time. "Southern gardeners are going to go crazy," Turner says. Both are medium-size deciduous shrubs with beautiful quilted leaves and large inflorescences covered with creamy white flowers that mature to rich, tawny pink. The blooms remain showy into fall. 'Munchkin' grows to 3 feet tall, and 'Ruby Slippers' is a little larger, up to 3-1/2 feet tall. They thrive in sun or shade. Zones 5-8 Learn more about hydrangeas.
Hybridizers working on the old-time favorite sweetshrub (Calycanthus) made a stunning breakthrough with 'Venus': the snow-white flowers look like miniature magnolia blossoms. Sweetshrub blooms primarily in spring; 'Venus' is a prolific-flowering hybrid that continues to produce fragrant, 3- to 4-inch flowers off and on all summer long. It was nominated as a 2011 Showstopper plant by the North Carolina Nursery and Landscape Association. This undemanding shrub flourishes in well-drained soil in sun or part shade and grows to 10 feet tall and wide. With judicious pruning, it can be kept to about 5 feet tall. The handsome leaves turn golden yellow in fall. Zones 5-9 Learn more about sweetshrub.
Fall- and winter-flowering camellias are the delight of southern gardens and gardeners, but it can be a challenge to find the right place for them. "They can be gawky in the landscape," says Scott Aker, horticulturist at the U.S. National Arboretum. Camellias are evergreen shrubs, pretty in mixed borders or woodland gardens. Camellia sasanqua 'Agnes O. Solomon' is one of Aker's favorites. This fall-blooming camellia has graceful, soft pink flowers. It grows slowly to about 6 feet tall in light shade and is hardy in Zones 7-9. Aker also likes C. japonica 'Anacostia', which was introduced by the U.S. National Arboretum. "It's wonderful, with a rounded habit, and it's hardier than most," he says. 'Anacostia' grows to about 12 feet tall. 'Anacostia' is hardy in Zones 7-9, and in protected areas in Zone 6. Learn more about camellia.
Rose of Sharon
Rose of Sharon (Hibiscus syriacus) comes into glorious bloom in midsummer with countless hibiscuslike flowers. Turner especially likes two newer groups: the Satin series (Azurri Satin, shown here, Blue Satin, Blush Satin, Rose Satin, and Violet Satin) and the Chiffon series (China Chiffon, Blue Chiffon, White Chiffon, and Lavender Chiffon), all of which have sterile flowers and will not self-seed. "People need to stop growing all the rest of the varieties and just grow these," he says. Rose of Sharon attracts butterflies and hummingbirds and looks great as a shrub or small tree; most varieties will grow 8-12 feet tall, but since they bloom on new growth, they can be pruned ruthlessly. "If you cut them back they grow to 4-5 feet tall," Turner says. For the best show of bloom, they need a spot in full sun. Zones 5-9 Learn more about rose of Sharon.