The Leyland cypress (x Cupressocyparis leylandii) is a pyramid-shaped evergreen that is a hybrid of the Alaskan cedar and the Monterey cypress. The Leyland cypress is a fast-growing tree, gaining up to 3 feet in height each year, often used for privacy hedges and even Christmas trees. Growing to a mature height of 75 feet or more and width of up to 25 feet, the Leyland cypress tolerates annual minimum temperatures down to about -10 to 0 degrees Fahrenheit. You should plant your Leyland cypress tree in full sun to light shade and in well-draining soil.
Pull out and remove all weeds or grass growing within 3 feet of your Leyland cypress right after planting the tree. Spread a 2- to 3-inch layer of bark mulch around this area to control weeds and retain soil moisture.
Apply a tree-root stimulator to your Leyland cypress right after planting to help the tree establish itself quicker. Follow the dosage and application instructions on the fertilizer's package.
Stake your newly planted Leyland cypress to protect it from damaging winds while the roots are becoming established. Insert a stake beside the cypress that is the same height as the tree and tie the tree loosely to the stake using three evenly-spaced twist ties or soft string.
Feed your Leyland cypress once per year in early spring. Select a slow-release fertilizer made for evergreen trees that has a nine- to 12-month release and follow the dosage directions on the package.
Water your Leyland cypress to supplement rainfall once per week during its first one or two years, or more often during dry spells or droughts. After that, cut back on water to two or three times each month during the growing season.
Prune your Leyland cypress once or twice each year after the new growth has hardened off and has a rougher texture. Remove all dead, diseased or damaged branches first, and then thin out any crowded, crossing or inward-growing branches, cutting the limbs back to the trunk.
Spray your Leyland cypress tree with a fungicide after pruning or shearing to prevent the open wounds from being infected by a fungal disease. Apply the fungicide once every seven to 10 days for about six weeks, according to the directions on the label.