A high hedge can shield your yard or garden from the wind or from the eyes of others. Low ones make attractive space dividers. For a dense hedge, space deciduous shrubs 1 to 11/2 feet apart, evergreens 11/z to 3 feet apart, depending on their size.
Some deciduous shrubs for tall hedges are the fast-growing buckthorn; the yellow-flowered Siberian pea tree; the thorny, white-flowered English hawthorn; and the silvery green Russian olive (a fast grower, good for seashores and dry areas).
Evergreens for tall hedges include the hardy, shiny leaved holly and the slow-growing yew, with its dark green needles and poisonous red berries. The Leyland cypress is fast growing, but survives only in mild climates. Hemlocks are winter-hardy but do not last long in hot climates or in city air. For short to medium hedges, try the deciduous barberry or the evergreen boxwood, cotoneaster, or privet.
Plant the young shrubs in a trench at least 1 foot deep and 11/2 feet wide. Before placing them, work 2 or 3 inches of compost or peat moss into the soil on the bottom, then cover with 2 or 3 inches of topsoil. Add some compost or peat moss to the soil you took out of the trench as well, along with superphosphate at the rate of 2 to 3 rounded tablespoons per foot of row. Position the plants and replace the enriched soil.
To encourage dense growth at the base of deciduous shrubs, cut them back to about 1 foot high after planting. If necessary, to keep young plants upright, tie them with soft twine to a wire strung between posts.
Until a hedge reaches its full height, prune back one-third to two-thirds of the new growth each year, making the plants a little wider at the base than at the top. One such annual shearing, while the plants are dormant, is usually enough. Privets and other fast growers may need a midsummer trim as well. Once the hedge is as high as you want it, prune new growth to 1 inch long.