Cotoneaster sp.

Common Name:

Cotoneaster

General information:

Pronounced “Cot-o-ne-as-ter,” the name is taken from the Greek “Kotoneon” (quince) and the Latin “ad istar” (similarity). Although it really doesn’t seem similar to quince, this plant is a popular shrub as well as a bonsai favourite. Some varieties of Cotoneaster are evergreen, some deciduous, and some, like the rockspray, will either retain their leaves or lose them depending on the climate.

Most Cotoneasters are prostrate shrubs which will also climb over rocks and walls, but a few - the most notable being C. frigidus - will grow into trees. All varieties are well-loved for their showy berries, and many Cotoneasters have attractive pink or white flowers as well. Coates points out that Cotoneasters have an advantage over most Pyracanthas - no thorns!

Lighting:

Varies according to variety, although most Cotoneasters prefer full sun.

Temperature:

Some varieties are occasionally used for indoor bonsai, but most successfully grown outdoors. Generally hardy to zones 6 or 7, but frost protection is advised. Most Cotoneasters do well in hot climates.

Watering:

The Samsons claim that Cotoneaster likes a dry soil - allow it to dry out a bit between waterings, then water it well. Tomlinson takes the opposite view - that the Cotoneaster should be kept moist at all times! Although Cotoneaster likes good drainage, it dislikes a dry atmosphere, and can benefit from regular misting.

Feeding:

Every two weeks until flowering, then monthly during growth. Use liquid bonsai fertilizer or half-strength plant food.

Pruning and wiring:

Cotoneaster likes to sucker, so if it is not being grown as a clump, suckers must be vigilantly removed to promote trunk growth. New shoots should be shortened to one or two leaves throughout the growing season. The Cotoneaster takes well to wiring, which can be performed just before bud break in spring. Protect the bark when wiring. Cotoneasters lend themselves to mame and shohin, but are harder to grow as large bonsai.

Propagation:

Cuttings may be taken in June-July, and should take about six weeks to root. Air-layering may be used as well; the most optimal time is during bud-swelling in the spring. Cotoneaster may be grown from seed collected from the berries in fall, but the Samsons claim that seed grown plants are inferior to other methods. The seeds must be cold treated and sown in early spring.

Repotting:

Annually in spring, using fast-draining soil. Up to a third of the roots may be removed. Cotoneaster does not like to be bare-rooted.

Pests and diseases:

Aphids, woolly aphids, scale, leaf blight, crown-gall and bacterial fireblight. A showy display of berries can be decimated by a hungry blackbird. C. horizontalis is particularly attractive to bees and wasps - which doesn’t bother the plant, but may be a risk to unsuspecting bonsaists!

Some species suitable for bonsai:

Cotoneaster adpressa - a deciduous cotoneaster with pink flowers, red fruit and good autumn color.

Cotoneaster adpressa praecox - similar to the above, but has better autumn color and brighter fruits.

Cotoneaster apiculata: cranberry cotoneaster .

Cotoneaster congesta: congested cotoneaster - an evergreen shrub with white flowers and red fruit. Very small, and especially good for mame.

Cotoneaster conspicuus decorus - Small-leaved evergreen with red fruit. Its most notable feature is its fragrant white flowers, which open fully to resemble wild roses. Another advantage - birds don’t seem to like the taste of this Cotoneaster’s fruit.

Cotoneaster dammeri: Skogholm cotoneaster.

Cotoneaster divaricatus: spreading cotoneaster - Native to China, this Cotoneaster grows to six feet. It has bright red berries pink flowers, and a fine show of autumn color before losing its leaves. Hardy in zones 5-8, it stands up to cold better than most Cotoneasters.

Cotoneaster horizontalis: rockspray cotoneaster - A broad-leaved shrub, hardy to zone six. The rockspray cotoneaster has white or pink flowers and very nice autumn colors in areas where it is deciduous. Its herringbone growth pattern and wide leaves are not typical of the genus, although it is one of the most popular varieties for bonsai.

Cotoneaster horizontalis ‘Variegatus’: varigated rockspray - less vigorous than the species, but has cream and green patterning on the leaves and pink fruit.

Cotoneaster integerrima: common cotoneaster.

Cotoneaster lucida: hedge cotoneaster.

Cotoneaster microphyllus - Recommended by Lesniewicz as a good candidate for indoor bonsai, this evergreen has white flowers and red fruit. Its slender, pointy leaves are glossy dark green.

Cotoneaster microphyllus ‘Cochleatus’: dwarf creeping cotoneaster - another good potential indoor bonsai.

Cotoneaster microphyllus ‘Thymifolius’: thyme-leaf cotoneaster - This plant has the smallest leaves of any Cotoneaster. It has pink flowers, red fruits, and is hardy to zone 7.

Cotoneaster multiflorus: many-flowered cotoneaster - A large and showy plant, this is the Cotoneaster to choose for large size bonsai. It has large, red, conspicuous fruit and showy clusters of white flowers. It grows to ten feet, and has two-inch leaves that turn yellow in autumn before leaf fall. Hardy in zones 5-7, another good cold-weather choice.

Cotoneaster simmonsii - This Cotoneaster can be deciduous or evergreen, depending on conditions. It has pink flowers, red fruit, and small, leathery leaves which may turn scarlet in autumn.

Cotoneaster ‘Skogholm’ - An evergreen dwarf, with large oval fruit, coral red in color.

Cotoneaster salicifolia (Willow leaf cotoneaster.) Small dark green leaves, very small pink flowers, bright red berries and reddish foliage in fall. Water heavily. Soil must be well drained and may become dry between waterings. Fertilize with half strength high phosphorus (middle number) fertilizer.

Bibliography:

Cotoneaster

Lesniewicz’s “Bonsai in Your Home”

Owen’s “Bonsai Identifier”

“Resnick’s “Bonsai”

Samson’s “Creative Art of Bonsai”

Tomlinson’s “Complete Book of Bonsai”

Species information from Coats’ “Garden Shrubs and Their Histories,” and Thomas (ed.) “The Hearst Garden Guide to Trees and Shrubs.”

Compiled by Sabrina Caine