Cornus x rutgeriensis a hybrid flowering dogwood, a cross between Cornus florida, found in the south-easter United States, and the Chinese Cornus kousa and was developed as one of the 'Stellar' dogwoods bred at Rutgers University in New Jersey.
It is vigorous and will form a large shrub, or small tree, in time, the rate of growth being determined sy soil fertility and the availability of moisture - broadly speaking the more of both, the better! Eventual height is likely to be in the range of 4-6m, and generally wider than it is tall, so plant with plenty of room for future growth.
'Ruth Ellen' produces exceptionally numerous large-bracted flowers from a young age during April to May, the bracts being pure white whilst the true flowers being insignificant and yellowish-green. Ruth Ellen is also sterlie so will not produce fruit, but on the other hand will put a lovely display of autumn colours, as the leaves turn to rich tones of plum purple.