Pennsylvania has a humid continental climate, with the northern regions experiencing cool summers and cold winters. If you live in northern Pennsylvania, choose your shrubs according to cold hardiness, bloom information, mature size and cultural requirements. Numerous flowering shrubs perform well in northern Pennsylvania landscapes. Northern Pennsylvania falls within USDA hardiness zones 4 to 6.
The bog rosemary (Andromeda polifolia), a clump-forming shrub in the heath family (Ericaceae), reaches anywhere from 8 to 36 inches in height and width. This perennial features thin, bluish-green leaves and tiny, pink or white blossoms that bloom in June and July. The bog rosemary tolerates various lighting conditions but requires moist to wet, strongly acidic soils. All parts of this plant contain toxic principles that can cause severe gastrointestinal and neurological reactions. Northern Pennsylvania gardeners sometimes plant the bog rosemary in acidic bog margins or bog gardens.
The chinkapin shrub (Castanea pumila), a beech family member (Fagaceae), naturally occurs in dry woods across northern Pennsylvania. This perennial reaches heights up to 30 feet and bears shiny, deep green leaves that turn purple or yellow shades in the autumn. Long, thin spikes of light yellow flowers bloom from March through June, followed by sweet, brown nuts that attract squirrels and deer. This shrub prefers dry, acidic soils that receive some shade. Chestnut blight sometimes occurs. Gardeners often use the chinkapin in wildlife gardens and open woodland areas.
Black huckleberry shrubs (Gaylussacia baccata) form colonies that reach between 12 and 24 inches high. Panicles of tubular, white or pale pink flowers bloom from May through July. These blossoms give way to edible, deep purple to black berries. This heath family member (Ericaceae) also bears small, green leaves that turn crimson or orange in the autumn. Northern Pennsylvania gardeners often use black huckleberry bushes in wildlife gardens or as groundcover for rocky woodland areas.
Shrubby St. Johns-Wort
The shrubby St. Johns-wort plant (Hypericum prolificum) adapts to a wide range of moisture conditions but likes sandy or rocky soils in shady locations. Reaching heights up to 3 feet, this shrub bears purple or red bark and smooth, bluish-green foliage that turns yellowish-green in the autumn. Big, yellow blossoms appear from June through August. This Clusiaceae plant family member generally performs well in northern Pennsylvania floodplains and meadows.
Bog Labrador Tea
Bog Labrador tea (Ledum groenlandicum), sometimes called rusty Labrador tea or muskeg tea, belongs in the heath family (Ericaceae) and reaches up to 3 feet in height. This evergreen shrub features hairy twigs and copper, orange or red-brown bark. Aromatic, grayish-green leaves feature fuzzy, brown undersides. These leaves are sometimes used to make teas. Clusters of white, bell-shaped flowers bloom from May through August. This shrub prefers wet, acidic soils in partially to fully sunny locations. Northern Pennsylvania gardeners often plant bog Labrador tea in peaty bog gardens or damp woodland gardens.