When & How to Prune & Fertilize Leyland Cypress Trees

Use hand pruners for Leyland cypress.

The fast-growing evergreen shrub Leyland cypress (Cupressocyparis leylandii) is a popular landscape choice. The shrub makes a nice privacy screen or hedge specimen, and averages 3 to 4 feet of growth per year. Leyland cypress trees grow in hardiness zones 6 to 10A. Mature specimens can reach 50 feet in height. Prune Leyland cypress trees twice each year to control the plant's size, shape and health. Fertilize to keep your cypress healthy and promote growth.

Things You'll Need

• Hand pruners
• Disinfectant spray

Instructions

1. Check your Leyland cypress tree for signs of dead, diseased or winter-damaged branches in February or March. These branches must be removed for the health of the tree and will look markedly different from healthy wood. Diseased or damaged branches may appear tan, swollen, bent or broken.

2. Cut off unhealthy wood at its base. Discard the unhealthy wood in a garbage bin. Sanitize your pruners between each cut by spraying them with disinfectant.

3. Trim back long branches to control the size and shape of your Leyland cypress tree. Naturally pyramid-shaped, Leyland cypress trees can look bushy if not trimmed back. Work one branch at a time, making cuts at a 45-degree angle.

4. Remove limbs that cross or compress other limbs. Prune one off at the base. Also remove wayward or downward-growing limbs that detract from the Leyland cypress tree's shape.

5. Fertilize your Leyland cypress with slow-release fertilizer in early spring, after pruning. Apply the manufacturer's recommended dose of 10-10-10 or 20-20-20 slow-release fertilizer, which is based upon the size of your cypress tree. Scatter dry-release fertilizer on the ground around your tree, then water the tree to disperse nutrients throughout the soil.

6. Allow the cypress to grow through the spring and summer.

7. Trim the Leyland cypress again in June. Cut long branches back to the desired height, maintaining the tree's shape and size. Remove any dead or damaged branches you find at this time, too.

References

• United States Forest Service: Leyland Cypress
• Polk County Center: Pruning Calendar
• Auckers Nursery: Fertilizing Leyland Cypress