Tall, narrow conifers are like exclamation marks in a landscape. They add a contrasting vertical element to deciduous trees and plants with rounded forms. They also can be used in pots to frame an entryway or other architectural feature and as hedge plants to screen an unwanted view or create an enclosure for the garden as a whole.
The Italian cypress (Cupressus sempervirens) is the traditional choice for a narrow, columnar evergreen and has been grown for hundreds of years. Glauca, with greyish-green foliage, grows quickly to 70 by 6 feet. It is hardy to -17.8 degrees Celsius and prefers full sun. A cultivar, Swane's Golden, grows to 20 by 3 feet. Tiny Tower grows very slowly to 30 by 3 feet, suitable for containers.
Columnar junipers have aromatic, prickly grey foliage and also prefer full sun. Juniperus virginiana Taylor grows 30 by 3 feet, Skyrocket grows quickly to 20 by 3 feet and Blue Arrow grows to 15 by 2 feet. Junipers are hardy to U.S. Department of Agriculture plant hardiness zone 2.
For shade, the Irish yew (Taxus baccata Fastigiata) is a narrow conifer with soft, dark green needles. It grows slowly to 30 by 4 feet in sun, part sun or shade. Aureomarginata, a variety with cream and green variegated foliage, grows more quickly. Yews are hardy to USDA zone 4.
Conifers are very drought-tolerant plants that need little water once established. During their first year, water them deeply and regularly during the dry season to promote a deep root system. This could mean watering twice a week in hot weather. Feed with an all-purpose 4-4-4 NPK fertiliser in spring before growth begins.