Leyland cypress trees (Cupressocyparis leylandii) are fast-growing, evergreen trees. These trees are a favorite with landscapers and home gardeners who want plants that will quickly form a privacy screen or barrier. Slender and conical in shape, these trees are attractive but somewhat weak. They often suffer from adverse weather, diseases and insect problems, according to Karen Russ, a horticulture specialist with Clemson University.
How Fast Do Leyland Cypress Trees Grow?
Leyland cypress trees grow very fast when first planted--up to 4 feet per year, according to Debbie Shaughnessy, a horticulturist with Clemson University. They can grow up to 100 feet tall and 20 feet wide if allowed to grow unchecked. Luckily, these trees can tolerate heavy pruning, so their rapid growth can easily be contained.
Where Can I Plant A Leyland Cypress?
Leyland cypress trees thrive in United States Department of Agriculture (USDA) growing zones 6 through 10a. These trees prefer slightly acidic soil but can tolerate almost any type of soil, from sandy to clay, as long as the soil is well-draining. Standing water will rot the shallow roots of the tree before it can become established. Choose a location that receives either a full day of sunlight, or at the minimum, a half-day of sunlight. Finally, plant your tree in a location where it is protected from heavy winds, which can often cause tall trees to split.
How Do I Treat Problems?
Treat your Leyland cypress with a systematic fungicide in the spring. Make sure to cover the entire tree. This will reduce the occurrences of common fungal diseases, including canker diseases, cercosporidium blight, and leaf spots. Root rots are more difficult to prevent, but if you keep the soil around your tree dry, it will reduce the chances that a fungus will live and thrive in the dirt. In addition, watch your tree carefully for signs of insect infestations, and spray your tree with an insecticide if you notice increased insect activity. Bagworm is especially damaging to Leyland cypress trees and can defoliate an entire tree in a matter of weeks. Many insects carry diseases and enter the Leyland cypress through wounds in the tree's tender bark, so take care not to damage it when pruning or mowing the lawn around the tree.
Which Cultivars Are Best?
"Castlewellan" is a smaller cultivar with attractive, gold-tipped foliage that thrives in cooler climates, according to Edward F. Gilman, a horitculturist with the University of Florida. "Leighton Green" is a dense cultivar with deep green leaves. "Silver Dust" makes an excellent hedge, as it is wide-spreading, and it also has an interesting, blue-green color with white variegation in the leaves.