Chamaecyparis obtusa 'Green Diamond' is a robust, large-growing, upright tree form of Hinoki cypress with dense branching, and dark-green, fan-shaped foliage with nodding tips. After 10 years of growth, a mature specimen will measure 10 feet (3 m) tall and two-thirds as wide, an annual growth rate of 1 foot (30 cm) or more.
This cultivar originated in the mid-1960s in the United States, and released under the illegitimate name 'Columnaris'. Propagation material was later sent to Konijn & Company Nursery, Boskoop, The Netherlands, who brought into production and introduced it to the European nursery trade with the name 'Green Diamond.