The spindle tree family (nishikigi-ka, Celastraceae) contains some very ornamental trees, shrubs and climbers, among which nishikigi, the genus Euonymus, is a large group encompassing some 176 species. They grow wild in the temperate to warm regions of the world and can be found in Australia, Europe and North and Central America. The chief concentration of Euonymus is in the Himalayan region and East Asia, including Japan. Some 15 species of Euonymus grow wild in Japan, but as in Europe only a few species are cultivated by gardeners.
There are both deciduous and evergreen Euonymus trees, shrubs and even an evergreen climber. Of the 15 Japanese species, 10 are deciduous and the rest are evergreen. The leaves are simple; some have smooth edges while others are serrated.
Flowers appear in spring and are small, inconspicuous and white, greenish or yellowish in color. They have from three to five petals and the stamens are in equal number to the petals. Flowers are normally bisexual, possessing both male stamens and female pistils on the same flower. In many species the flowers are borne in cymes made up of three to seven (sometimes 15) small flowers.
The fruit are fleshy capsules. When ripe they burst open into five valves, each containing from one to four red, white or black seeds which are enclosed by a brilliant orange or scarlet aril. The fruit in autumn is truly beautiful, but beware: The seeds of all species are believed to be poisonous.
The Japanese spindle tree (nishikigi, Euonymus alatus) is a wide-spreading deciduous shrub. Flowers appear in May. The cyme, each approximately 2 cm wide, contains only a few flowers. The stems are green and covered with corky wings which add to the plant’s beauty.
The chief attraction of the nishikigi (literally, “brocade tree”) is the beautiful display of leaves and the fruit enclosed in a bright vermilion aril in autumn. The leaves of this spindle tree are very thin, with finely serrate edges. It grows wild from Hokkaido down to Kyushu, but varies a lot. There is a wild form called ke-ko-mayumi (E. alatus forma apterus) that has no cork on the branches.
Tsuribana (E. oxyphyllus) is a large deciduous shrub or small tree. In the autumn the leaves turn nice shades of red and the fruit is encased in a very showy scarlet red aril. In Japan, tsuribana has a very similar distribution pattern to nishikigi.
Otsuribana (E. planipes) is another deciduous shrub with good autumn color. Since Otsuribana can withstand low winter temperatures, the species is not surprisingly found in the northern half of Honshu, Hokkaido, northeast China and eastern Siberia. The flowers, white to pale green, are borne in May-June and hang in groups of 10 or more.
Of the five native evergreen species two are not only well known in Japan but are also very commonly planted in the U.S. and Europe. Masaki (Euonymus japonicus) is a large shrub that grows to a height of 2-6 meters, with numerous cultivars. The upright habit of masaki makes a nice hedge, informal rather than closely clipped, due to the tough, leathery texture and leaves’ serrated edges. This widespread plant is particularly common in coastal woods in Japan, as well as in Korea and China.
The second popular evergreen species is tsuru-masaki (Euonymus fortunei), an evergreen climber. The first time I ever saw this climbing euonymid in its native habitat was on Mount Katsuragi in southern Osaka. There the tsuru-masaki was happily growing way up the trunk of a tall Japanese beech tree (buna, Fagus crenata). More recently, while I was walking through the Kitanomaru Park on the outskirts of the Imperial Palace, I saw a young tsuru-masaki climbing the trunk of a konara deciduous oak (Quercus serrata).
Often planted as a ground-cover plant, tsuru-masaki will tolerate both shade and direct sun. Perhaps the most popular cultivar is “Emerald ‘n’ Gold,” which originated in 1967 in Gloucester, Mass. The leaves are green with a broad yellow margin; during the cold winter months, they turn a pink or reddish color. “Silver Queen” has butter-yellow-colored leaves turning to grayish green with a creamy white margin. This cultivar grows to about 1 meter in height and is ideal for growing in containers.
Because of their relatively thick leaves, the evergreen species of Euonymus are tough and tolerant of pollution and sea winds. Any fertile, well-drained soil will be sufficient. Sometimes branches on the cultivated garden forms may revert to the original green color; when this happens, remove the green branch as soon as it appears. During the summer months, Euonymus japonicus is prone to attacks by powdery mildew.
Some species of Euonymus yield useful products. The name spindle tree comes from the European species Euonymus europaeus, which is a deciduous shrub similar to the Japanese species tsuribana. The wood from the European species, which is fine grained and very durable, was widely used for figure carving as well as making spindles, hence the name.
In Japan, mayumi (E. Sieboldianus), a deciduous species, produces heavy, durable wood used for printing blocks and in the turnery. A rubberlike latex is produced by the roots and stems of masaki and mayumi.
Propagation of the deciduous species is best achieved with seeding. First, collect the seed capsule when it is about to open. Next, separate the orange-colored aril from the seed. Sow the seed immediately in small pots, and finally plunge the pots into the ground where you raise other garden seeds.
Evergreen species can be propagated by stem cuttings, taken during October and November. The stems should be 10 cm long when they are cut by the bud. The compost for the cuttings should be made of two parts peat moss and one part sand.
May your planting be successful.