Culture
Grow in acidic, organically rich, medium moisture, well-drained soils in full sun to part shade. Some afternoon shade is appreciated in hot summer climates such as the St. Louis area. Best performance occurs in cool summer climates. Provide consistent moisture and mulch root zone.
Noteworthy Characteristics
Cornus controversa, commonly called giant dogwood, is a rounded, medium-sized, deciduous tree that will grow somewhat rapidly to 35-40’ (less frequently to 60’) tall with distinctive horizontal branching in tiers. This tree and C. alternifolia are the only dogwoods that feature alternate leaves. Small, creamy-white flowers appear in flattened clusters (cymes to 3-7” wide) in late spring (May-June). Although individual flowers are small, a tree in full bloom is quite showy. Flowers give way to clusters of bluish-black fruits (drupes to 1/2”) that mature in late summer. Fruits are attractive to birds. Ovate dark green leaves (3-6” long) are glaucous beneath. Fall color is variable but usually not showy, ranging from at best a respectable red-purple to a more typical pale green and yellow.
Genus name comes from the Latin word cornus meaning "horn", possibly in reference to the strength and density of the wood. Cornus is also the Latin name for cornelian cherry (Cornus mas). May also be related to the Greek kerasos meaning "cherry".
'Variegata' is a cultivar which features green leaves with showy creamy white margins.
Problems
Susceptible to leaf spot, root rot and canker. Scale, leaf miner and borers are occasional insect pests. Unlike C. alternifolia, this species is resistant to twig blight.
Uses
Lawn tree.
Variegated foliage, spring flowers, summer fruits, fall color and distinctive branching give this dogwood year round interest.