The Leyland cypress is an evergreen conifer that reaches a height up to 100 feet and forms a column or narrow pyramid shape. The tree is a hybrid variety of cypress that was created in Great Britain and is known for fast growth, which is why they are planted in groups to form windbreaks and privacy screens in residential areas. Propagate a Leyland cypress by taking stem cuttings during the winter dormant months of January through March and placing them immediately into a rooting environment.
Take a 6- to 8-inch stem cutting with a sharp knife from a Leyland cypress tree that is under the age of 10. Keep the cuttings in a cool, moist location until they are stuck into a rooting medium.
Fill 3-inch diameter rooting containers with a mixture that has equal parts peat moss and perlite. Make sure the containers have bottom drainage holes. Moisten the medium with water and make a 2-inch deep hole in the mixture to stick the stem cutting in.
Remove the leaves from the bottom 2 inches of the stem cuttings. Dip the bottom end of the stem in a rooting hormone powder and gently tap to remove excess. Stick the cutting into the hole made in the rooting medium. Gently firm the medium around the cutting to hold it in place.
Place the rooting container in a warm, humid environment with a misting system. The temperature should be approximately 69 degrees F with the mist set for every five minutes. Cover the container with a plastic bag and manually mist the cuttings several times a day if an automatic misting environment is not available.
Monitor the cuttings for root development, which may take six to eight weeks. Apply a 20-20-20 liquid fertilizer that is diluted to half-strength once the roots appear on the cuttings.
Transplant the cuttings once roots have development to1 to 2 inches in length. Fill a 6-inch potting container with sterile potting soil and plant the cuttings at the same depth they were in the rooting containers.