Few, if any, species of Euonymus have any beauty of flower. Their value in the garden dwells in the beauty of their fruits, in the autumnal colours of the foliage of some species, and in the rich evergreen foliage of others. They are evergreen or deciduous trees, shrubs, or creeping plants, with the young shoots often four-angled. The leaves are always opposite and toothed in the cultivated species, except E. nanus. The arrangement of the flowers is very characteristic in this genus; they are borne from May to June in cymes from the lower joints of the current season’s growth. There is first a slender main-stalk usually about 1 in. long, which terminates in a single flower flanked by one at each side. This three-flowered cyme is seen in E. europaeus and others; but often the main-stem, instead of producing two side flowers, forks into two parts, each with its terminal flower and two side ones. The inflorescence is then seven-flowered. Sometimes these secondary stems branch again and the inflorescence becomes fifteen-flowered.
The flowers are usually from 1⁄6 to 1⁄3 in. across, greenish, yellowish, or white, rarely purple. The parts of the flower (sepals, petals, stamens, and lobes of the fruit) are in fours or fives, which sometimes afford a convenient means of distinction. The fruits are pendulous and highly coloured, and are composed of three to five one-seeded cells or lobes – the lobes often angled, sometimes winged. The seed is partially covered with an outer coat known as the aril, which is usually brilliantly coloured – scarlet, orange, etc., and adds much to the effect of the fruit when the cells burst.
The only other genus of hardy shrubs with which Euonymus can be confused is Celastrus, which has a similar fruit, but is well distinguished by its alternate leaves.
These plants are easily cultivated in a good, well-drained loam. Some of the species, e.g. E. atropurpureus and americanus, like a position shaded during the hottest hours of the day, and all the evergreen sorts grow, if they do not bear fruit well, in permanent, if not too dense, shade. Propagation of the deciduous species is best effected by seeds. Failing this method, cuttings or layers may be used; cuttings of the evergreen species and varieties take root very readily, and may be struck at almost any season if a little bottom heat is given.
Several species, notable E. europaeus and japonicus, are frequently badly attacked by a caterpillar at the flowering season, which swarms on the branches in cobwebby masses, feeding on the leaves and preventing the formation of a crop of fruit. A quick and effective remedy is to spray with some modern contact insectide.
From the Supplement (Vol. V)
A survey of the cultivated species by Roy Lancaster will be found in The Plantsman, Vol. 3(3), pp. 133-66 (1981) with supplementary notes in Vol. 4(1), pp. 61-3 (1982) and Vol. 4(4), p. 253 (1983). The evergreen species and cultivars (mostly of E. fortunei) are assessed by Harry van de Laar in Dendroflora No. 15/16, pp. 9-23 (1979).