Shrubs for an Informal Hedge

Hydrangea

• These moisture loving shrubs thrive in humusy soil. Hydrangeas (Hydrangea spp.) tolerate partial shade or sun and may die back in the winter. The best feature of hydrangeas is the large, old fashioned flowers that cover the bushes. The flowers turn pink in alkaline soil and blue in acid. Hardy to Zone 4, Pegee hydrangea (Hydrangea paniculata grandiflora) grows quickly to form a large tree- like shrub, 7 feet high and 5 feet wide. Prune hydrangea hedges lightly in early spring, cutting out dead branches. To shape the shrubs, wait until after they finish blooming.

  The oak-leaf hydrangea (H. quercifolia) is a smaller shrub, suitable for short hedges (5 feet high and 4 feet wide). Hardy to USDA Zone 6, this plant isn't suitable for cold climates. Hydrangeas grow moderately fast and will reach full size within three to four years.

Lilac

• Lilacs (Syringa) are beloved for their fragrant blossoms that appear early in spring. They are easy to grow in most climates and, if left unpruned, can grow 20 feet tall and 6 feet wide. The common lilac (Syringa vulgaris) has purple, white, lavender or rose flowers, and is hardy to Zone 3. Lilacs grow slowly, but are long-lived. White powder on the leaves is powdery mildew, which is unattractive, but harmless.

  Prune lilacs in early spring, but only after they are well established. Cut out dead growth and most new suckers. Pinch off spent flowers to promote good blooming.

Spirea

• Spirea (Spiraea) grow easily almost anywhere; several varieties are available. An excellent choice for hedges, the fast growing snowmound spirea (S. nipponica) has gracefully arching limbs that are covered with small white flowers in the spring and early summer. They spread quickly and grow to about 5 feet tall and 3 feet wide. Give snowmound spirea plenty of room to spread out (4 feet between plants). Prune lightly after it blooms to remove dead wood.

Oregon Grape Holly

• Oregon grape holly (Mahonia aquifolium) grows indigenously throughout the Northwestern United States and was discovered by Lewis and Clark as they traveled through that region. Oregon grape holly has shiny, deep green leaves and waxy, blue berries in the summer. In the winter, its leaves turn maroon.

  The plants spread quickly through underground branches and can reach 5 feet in height and 3 feet in width. They have an open, leggy growth habit and require little pruning. Prune awkward branches to the ground in late spring. This plant makes a good privacy hedge, as its prickly leaves discourage animals and intruders. Oregon grape holly is hardy to Zone 5.

Viburnum

• Viburnums (Viburnum spp.) are among the easiest shrubs to grow. They tolerate some shade, but flower best in sun. In the spring, most varieties bear large clusters of white flowers. They produce berries in the summer and brilliant red foliage in the winter. American cranberry bush (V. trilobum) is a good choice for hedges. Hardy to Zone 3, it grows quickly and stands 6 feet tall and 4 feet wide. Korean spice viburnum (V. carlessii) is more compact than most species (5 feet tall) and is hardy to Zone 5. Viburnums require little pruning, beyond an occasional thinning.