Many attractive shrubs thrive across Pennsylvania's USDA hardiness zones 4 through 7. Using some of them in your Keystone State garden will provide a continuous stream of color with spring and summer blooms, attractive berries or fruit and autumn foliage. Shrubs recommended for Pennsylvania vary from low plants good for foundation plantings and small yards to tall plants that make great privacy screens or eye-catching single specimens.
Small Shrub: Glossy Abelia
Glossy abelia (Abelia grandiflora) is recommended for Pennsylvania by Penn State University. Standing 3 to 6 feet tall--and equally wide--this spreading member of the honeysuckle family has arching branches with abundant clusters of fragrant white to pale pink, bell-shaped flowers from May to frost. They contrast effectively against glossy, deep green leaves that become purplish-bronze in autumn.
In parts of Pennsylvania where winter temperatures drop to minus 15 degrees F and below for extended periods (USDA hardiness zones 4 and 5), plants may die back to the ground. They recover in spring, but usually remain between 12 and 18 inches high. Plant glossy abelia in sun to partial shade and moist, acidic, well-drained soil.
Medium Shrub: Beautyberry 'Early Amethyst'
Beautyberry 'Early Amethyst' (Callicarpa dichotoma 'Early Amethyst') lives up to its name. Standing 3 to 4 feet high and up to 5 feet wide, this round, deciduous shrub has arching branches that may touch the ground. Its lavender-pink clusters of small flowers appear above medium-green leaves between June and August. The shrub's crowning glory, however, is in the clusters of large, vivid purple berries that adorn it. They arrive in late summer and reach their peak in October, when many garden plants have already given up the ghost. Birds feed on them.
Like glossy abelia, beautyberry may die back in USDA hardiness zone 4 or 5 parts of Pennsylvania during the winter. It will re-emerge in the spring. Massing this shrub for cross-pollination will ensure maximum bloom and berries. Plant the shrub in full sun to partial shade and average, medium-moist soil. Late winter or early spring pruning will promote new wood on which the flowers grow.
Large Shrub: Smooth Azalea
A Lady Bird Johnson Wildlife Center recommended shrub for Pennsylvania, smooth azalea (Rhododendron arborescens) stands between 8 to 12 feet high and wide. A deciduous shrub, it has bright green leaves that become red or purple in autumn. Showy, fragrant clusters of white to pale pink, tubular flowers with protruding red stamens bloom in June and July, later than most garden azaleas. Plant swamp azalea in a partially shady spot with moist, acidic, well-drained soil. All parts of this shrub are toxic if ingested.