Colorful and reliable flowering shrubs dress up gardens in the Northeast from spring through frost. Bright yellow forsythia is always one of the first shrubs to bloom in spring, and you'll see it everywhere. To make your own garden more interesting, look around your neighborhood and try to plant something the neighbors don't already have, suggests Scott Aker, horticulturist at the U.S. National Arboretum in Washington, D.C.
Aker's favorite flowering shrubs for the Northeast include native plants and hardy, adaptable nonnatives. He likes shrubs with a long blooming season, fragrant flowers, interesting structure, and bright fall foliage color. Native shrubs -- including native azaleas -- are sometimes neglected, Aker says. However, they are not difficult to work into a garden: All plants need extra watering and attention when they are first planted, but once they are established, native plants usually need no pampering.
Plantsman and author Michael Dirr says: "A garden without a viburnum is akin to life without music and art." But there are about 150 different species of viburnums, and gardeners can be hard put to decide which is best. Aker's choice is Korean spice viburnum (V. carlesii) for its spring display of fragrant, white flowers. The attractive flower buds are pink or nearly red, and open to white in midspring. "It's a tough plant," Aker says, and the fall foliage is wonderful, too. Korean spice is hardy in Zones 4-8. Bill Thomas, director of Chanticleer Gardens in Wayne, Pennsylvania, also likes smooth witherod (V. nudum); one of the best cultivars is 'Winterthur' from the Winterthur Gardens in Delaware. Of the two, Korean spice viburnum has the showiest flowers and the strongest fragrance; plant it near the front walk, where you can enjoy the flowers as you come and go. Zones 5-9 Learn more about viburnums.
Buttercup winter hazel
Buttercup winter hazel (Corylopsis pauciflora) has soft yellow flowers, "a break from the brassy yellow of forsythia," Aker says. Clusters of dangling yellow flowers appear in early spring and last for about two weeks in cool weather. "It goes with a lot of things," including pink saucer magnolia (Magnolia soulangeana), which blooms at about the same time. Buttercup winter hazel is a small shrub, spreading to about 4 feet tall and wide. It has small, beautifully pleated leaves and a rather delicate appearance, but it is a tough shrub. Plant it in part shade. Zones 6-8
Spring-blooming azaleas put on a dazzling show every year in the dappled light under tall trees. Aker likes them all, but says "gardeners kind of neglect the native rhododendrons that are deciduous." He recommends Pinxterbloom azalea (Rhododendron periclymenoides), a deciduous shrub known for its white, pink, or violet flowers in early spring. This native azalea grows naturally on the banks of streams and in woods, and looks very pretty under trees in woodland gardens. It grows up to about 6 feet tall and is "amazingly drought-tolerant," Aker says. The coast azalea (R. atlanticum) is smaller but somewhat hardier, to Zone 5. Hybrids of these two species are known as the Choptank hybrids. Zones 4-8
Sometimes a native shrub just needs a little polishing to make it a better garden specimen. Hybridizers turned their attention to native ninebark (Physocarpus opulifolius) and produced some great-looking new plants for hedges and mixed-shrub borders, Thomas says. He especially likes the hybrid Diabolo, which has purple foliage, in sharp contrast to the spring flowers. Summer Wine also has dark purple leaves, but grows shorter (and Little Devil, at 4 feet, is even smaller yet). Coppertina, with orange-copper foliage, is a particularly splashy introduction. They all have pretty puffs of white flowers in late spring. Ninebark grows 4-8 feet tall (but tolerates hard pruning), and thrives in sun or part shade. They are adaptable and easy to grow. Zones 3-8 Learn more about ninebark.
Slender deutzia (Deutzia gracilis) looks like a little snowstorm when it comes into bloom in spring, with tiny white flowers that seem to cover the plant for up to two weeks. Deutzia grows slowly to about 3 feet tall and spreads up to 5 feet; it makes a handsome groundcover in front of a low wall or along the front edge of a mixed border in part shade or sun. Plant it with spring-flowering bulbs, and the deutzia will hide the bulb foliage as it matures and fades. 'Nikko' was introduced by the U.S. National Arboretum. It can also be grown to tumble gracefully over a wall and looks nice in pots. Chardonnay Pearls has striking yellow foliage. Zones 5-8 Learn more about deutzia.