Also known as Japanese cedar, cryptomeria is a slow-growing evergreen tree that is drought tolerant. Cryptomeria prefers to grow in full sun and in well-drained soil. The tree thrives when planted in USDA Hardiness Zones 5 through 9. Cryptomeria will reach heights of 50 feet with a 25-foot spread at maturity. Planted in most landscapes for its ornamental value, Japanese cedar develops coppery foliage in the fall and requires little care once its roots are established.
Water the cryptomeria generously after planting. Use a soaker hose to deliver deep watering. Keep the soil moist to a 1-inch depth at all times during the first growing season. Supplemental watering in lieu of rain is usually all that is necessary once the tree is established. Deep, once-a-week waterings are best during the summer months.
Feed the cryptomeria a diet of all-purpose fertilizer. Follow the label instructions on the fertilizer packaging for allocation amounts and frequency. Most Japanese cedar trees appreciate a dose of fertilizer prior to the development of new growth in the spring.
Prune the cryptomeria in the early summer. Remove dead, damaged, inward-growing or diseased branches with a pair of pruning shears or a pruning saw. Pruning will help the cryptomeria keep its pyramid-like shape and also encourage new growth.
Treat leaf blight with a fungicide. Cryptomeria trees are prone to diseases such as leaf blight and respond well to the application of a fungicide during the morning hours. Follow the instructions on the fungicide for the recommended application procedures.
Provide the cryptomeria tree with plenty of air circulation to prevent disease. Pulling weeds that grow under the canopy of the Japanese cedar will help improve airflow. A 3- to 4-inch layer of pine bark or straw can help prevent weeds from growing back. Mulching also improves water retention.