About
Sorbus alnifolia, the Korean mountain ash, is a large, deciduous tree to 20 m with dark-green, ovate leaves on red leaf-stalks turning yellow in autumn, white flowers 1 cm wide in spring and clusters of berries turning from orange to red in autumn, persisting after leaf fall. A handsome and rewarding ornamental tree for a sunny, well-drained garden.
About the genus
Sorbus, the mountain ashes, rowans and whitebeams, are deciduous trees or shrubs producing simple or pinnate leaves and clusters of small, white or pink flowers followed by white, yellow, pink, red or brown berries; many provide excellent autumn colour. Rewarding and ornamental trees and shrubs for a sunny, well-drained garden.
Growing conditions
SunlightFull sun, Partial shade
Soil typeLoam, Sand
Soil pHAcid, Neutral
Soil moistureWell-drained
AspectSouth-facing, North-facing, East-facing, West-facing
ExposureExposed, Sheltered
UK hardinessH5
Plant details
Plant typeTrees
HabitBushy
FoliageDeciduous
HeightHigher than 12 metres
Spread4-8 metres
Time to full height20-50 years
Suggested usesWildlife gardens
Native toE Asia
ToxicityFruit are ornamental, not to be eaten. Wear gloves and other protective equipment when handling. Pets: Fruit are ornamental, not to be eaten - see the HTA guide to potentially harmful plants for further information and useful contact numbers
Care notes
CultivationGrow in moderately-fertile, humus-rich soil. Tolerant of atmospheric pollution; ideal specimen tree in small garden, wild or woodland garden
PruningPruning group 1
PropagationPropagate by seed, softwood cuttings or grafting
Pest resistanceMay be susceptible to aphids, scale insects, pear blister mite, red spider mite and sawfly larvae
Disease resistanceMay be susceptible to fireblight, apple canker, silver leaf and honey fungus