Leyland cypress is a fast-growing pyramid-shaped evergreen that grows three feet per year. This growth rate makes it popular in landscape design, and is often used as a privacy screen, windbreak or hedge. Care of the Leyland cypress tree begins with choosing the correct site, as well as planting, watering, fertilization and pruning requirements. You should also be aware of the pests and diseases that the Leyland cypress is susceptible to.
The foliage of a young Leyland cypress is green; as the tree matures, the needles turn a dark/bluish green. Foliage is feathery and soft, and the needles give off a pleasant fragrance when broken. The needles retain their color throughout the year. The structure of the Leland cypress is dense (that is another reason it is used as a privacy screen or windbreak). When mature the Leyland cypress can reach a height of approximately 70 feet.
Site Selection and Planting
This evergreen prefers full sun to light shade. It will tolerate most soil conditions, with a soil pH between 5.5 to 6.5. If planting in sandy soil, add organic material so that the planting site will retain both water and nutrients. Choose a planting site with well-drained soil. Plant the Leyland cypress at the same depth that it was originally planted. Planting it at a deeper level can cause stem rot and tree death. Add 3 to 4 inches of mulch around the circumference and out to the drip line of the tree after planting to help maintain moisture and keep weeds down.
Watering and Fertilization
A newly planted tree should be watered twice a week; if weather conditions are extremely hot, you may have to water more frequently. The Leyland cypress is drought tolerant. However, if you are in an area that is extremely dry, you will need to make sure that the tree receives adequate water (drip irrigation is suggested). Lack of sufficient water lowers the growth rate. Established trees should be fertilized twice a year (spring and fall) with an 18-8-8 plus trace mineral fertilizer following the manufacturer's directions. (Trace minerals are also called minors.)
There are several reasons to prune the Leyland cypress: to remove any dead, diseased or damaged branches, and to maintain its shape and space within your landscape design. Dead, diseased or damaged branches can be removed at any time. Remove them as soon as possible to limit the spread of disease. The best time to trim or shear the Leyland cypress is when the new growth begins to mature (late spring to early summer). A late summer or early fall trimming may also be necessary to maintain its shape and size. If you want the tree to maintain its pyramidal shape, do not cut back the leader, but trim only the sides, and never remove more than 3 to 4 inches of growth.
Pests and Disease
The Leyland cypress is susceptible to infestations by bagworms and spittlebugs, juniper scale, cypress weevil, bark beetles and spruce spider mites. Diseases that affect this tree are seiridium canker, cercospora needle blight and botryosphaeria canker. The best defense against pests and disease is to maintain a healthy tree. Healthy trees are less susceptible, and if they are infested by pests or attacked by disease, they are better able to recover.