Paul Cappiello, horticulture director at
Bernheim Arboretum and Research Forest
in Clermont, Kentucky, responds: The landscape screen is one of the workhorses of the garden, providing a backdrop for other plants or concealment of an unpleasant view. Your choice of screening material is limited in a shady location, particularly if you have your heart set on a traditional sheared hedge. If you can use a less-formal planting, however, a number of species are useful.
I use Japanese hollies (Ilex crenata ‘Sky Pencil’) in my own garden because I can’t afford a great deal of lateral space for the screen. At maturity, this shrub is 10 feet tall, but only 3 feet wide. It has dark-green, glossy leaves typical of evergreen hollies.
Three yew (Taxus X media) cultivars make good screens in the shade, as long as there is excellent drainage and deer aren’t a problem. ‘Hicksii’ is a very large yew, growing as tall as 25 feet at maturity and almost as wide. ‘Hatfieldii’ reaches only half that height and width. Although large, these yews can be sheared to control their size and shape. The extremely narrow cultivar, ‘Flushing’, doesn’t require shearing and will reach a height of 15 feet.
The Japanese plum yew (Cephalotaxus harringtonia ‘Duke Gardens’) is one of the most shade-tolerant and gardenworthy evergreens available. The soft, black-green foliage is less appealing to deer than the foliage of yews is. ‘Duke Gardens’ reaches a height of 4 feet at maturity, so it is useful only as a short screen. Cephalotaxus fortunei, on the other hand, can grow up to 30 feet tall and 15 feet wide and, when pruned, is useful in a more formal shade setting.
If you want an informal screen with conspicuous flowers, try the rosebay rhododendron (Rhododendron maximum). Faster growing than other screening plants, this rhodie can reach up to 15 feet tall and at least as wide. Trusses of rose, purplish-pink, or white flowers appear in the summer.
If you are up to a challenge, try Daphniphyllum macropodum. It is one of the most densely foliaged and texturally enigmatic plants in my garden. It has the appearance of a dense rhododendron but without the flowers. It eventually reaches a height of 20 feet, with nearly the same width.
The dense branching of some deciduous and semi-evergreen shrubs creates an effective screen, even in winter. The leatherleaf viburnum (Viburnum rhytidophyllum) has creamy-white flower clusters in late spring, followed by red berries in fall that ripen to a glossy black. Leatherleaf viburnums create an informal hedge that will eventually grow to be 15 feet high and 12 feet wide.