The lemon cypress (Cupressus macrocarpa Goldcrest) is a cultivar of the striking Monterey cypress, native to the California coast. With softly scented, yellow to lime foliage, it grows in a narrow, columnar shape to 16 fee in height. Although it is sold outside of its hardiness zones as a houseplant, the lemon cypress generally won't thrive in dry, indoor air. Lemon cypress trees should be planted in full sun in USDA hardiness zones 7a to 10b.
Stake the young lemon cypress if the planting site is exposed to high winds.
Water the lemon cypress when the top 2 inches of soil is dry. Water slowly and deeply. A soaker hose set for two to three hours will suffice. Water more frequently during periods of hot weather.
Fertilize the lemon cypress in the spring. Use a 10-8-6 granular fertilizer, at the rate suggested on the package. Rake the soil, within a 3-foot radius of the tree, and spread the fertilizer over the raked area. Rake the area again to mix the fertilizer into the top 1/2 inch of soil. Water the lemon cypress after fertilizing.
Inspect the lemon cypress tree periodically for signs of pests. Aphids and mealybugs are attracted to the lemon cypress. Control infestations with insecticidal soaps, according to the instructions on the label.
Check the lemon cypress tree periodically for signs of coryneum canker fungus. Symptoms are similar to cold damage, with dieback of branches. Cut out diseased bark and destroy it. Removal of the tree may be necessary if the infection is widespread.