Photo credit: Dr. Susan Hamilton, University of Tennessee

Gyokuryu Japanese cedar (Cryptomeria japonica ‘Gyokuryu’) is a dense, broadly pyramidal evergreen shrub (USDA hardiness zones 5-8). It has short stiff needles that tend to be a slightly darker green than other cryptomeria cultivars. Gyokuryu holds its dark green color through most winters in zone 7 and further south. Expect winter bronzing when Gyokuryu is planted on high windy sites. Branches are pliable and release heavy snow to prevent limb breakage.

Spring/summer growth rate is moderate. Gyokuryu starts out as a short ball-shaped shrub, flattened on top. After 3 to 4 years it develops a dominant upright leader and takes on a pyramidal form. Gyokuryu grows 15 to 20 feet high and 5 to 7 feet wide in 20-25 years. Growth rate ranges from 6 to 9 inches per year. Over the years it becomes a handsome stand alone specimen plant, or you can group several together as a hedge or privacy screen.

Cryptomerias are planted in full sun and in an average well-drained, moderately acidic pH soil. One to three year old plants benefit from mulching. Disease and pest problems are minimal when plants are properly sited and not overcrowded. It is best to plant them 5-6 feet apart and allow them to gradually to fill in on their own. Two year established plants exhibit better than average drought tolerance. Supplemental irrigation during prolonged dry spells over 3 or more weeks is recommended for total optimum growth.

Deer generally stay away from cryptomerias. Feed in late winter and repeat in late spring with water soluble fertilizer (Miracle Gro™, Jacks™, or equivalent); or a granular fertilizer such as 10-10-10 or equivalent. Hollytone™ is a reliable evergreen plant fertilizer.