Culture
Best grown in average, medium moisture, well-drained soils in full sun to part shade. Prefers moist, organically rich, acidic soils in part shade. Benefits from a 2-4” mulch which will help keep roots cool and moist in summer.
Noteworthy Characteristics
Cornus is a genus of about 45 species of mainly deciduous shrubs and small trees.
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".
'Rutdan', being sold as CELESTIAL (originally given the trademark name of GALAXY) is a hybrid dogwood (Cornus florida x Cornus kousa) that was developed by Elwin R. Orton, Jr. as part of the Stellar series of dogwoods released by Rutgers University. It is noted for its vigorous habit, large-bracted flowers, profuse bloom and resistance to anthracnose and dogwood borer. It is a small deciduous tree with a dense, upright habit. It has a generally uniform width from top to bottom, typically maturing to 14-18’ tall and to 12-15’ wide. Flowers bloom in spring. The true dogwood flowers are actually tiny, yellowish green and insignificant, being compacted into button-like clusters. However, each flower cluster is surrounded by four showy, petal-like, white bracts which open flat, giving the appearance of a single, large, 3-5” diameter, 4-petaled, white flower. Floral bracts on this cultivar are obovate-rounded and slightly overlapping. Bracts emerge white with a green tinge, but mature to pink. Oval to elliptic, dark green leaves (4-5” long) turn attractive shades of purple-red in fall. CELESTIAL is sterile and does not produce fruit. It is sometimes sold in commerce under the name of Cornus x rutgeriensis. U.S. Plant Patent PP7,204 was issued on March 27, 1990.
Problems
Dogwood, when stressed, is susceptible to a rather large number of disease problems the most serious of which is dogwood anthracnose. Also susceptible to leaf spot, crown canker, root rot, powdery mildew and leaf and twig blight. Stressed trees also become vulnerable to borers. Leaf miner and scale are less serious potential insect pests. Leaf scorch may occur in full sun locations, particularly in hot, windy or droughty conditions.
CELESTIAL is noted for having good resistance to anthracnose and borers.
Uses
Popular as a specimen or small grouping on residential property around homes, near patios or in lawns. Also effective in woodland gardens.