Sorbus americana
American mountain ash
A fairly slow-growing tree with a rounded crown and light green leaves comprising up to 15 leaflets, turning red or yellow in autumn. In late spring and early summer produces dense, flattened clusters of small white flowers, followed by orange-red berries
Size
Ultimate height
8–12 metresTime to ultimate height
20–50 yearsUltimate spread
4–8 metresGrowing conditions
Moisture
Moist but well–drained, Well–drainedpH
Acid, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | White | Green | ||
|---|---|---|---|---|
| Summer | White | Green | Red | |
| Autumn | Red Yellow | Red | ||
| Winter |
Position
- Full sun
- Partial shade
Aspect
South–facing or East–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H6Botanical details
- Family
- Rosaceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Spreading branched
- Potentially harmful
- Fruit 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
- Genus
Sorbus can be deciduous trees or shrubs with simple or pinnate leaves and clusters of small white or pink flowers, followed by white, yellow, pink, red or brown berries; some have fine autumn colour
- Name status
Correct
- Plant range
- Eastern N America
How to grow
Cultivation
Prefers moist but well-drained, acid or neutral soil in full sun or light, dappled shade
Propagation
Propagate by seed sown in containers in a cold frame in autumn or by taking semi-ripe cuttings in early summer
Suggested planting locations and garden types
- City and courtyard gardens
- Cottage and informal garden
- Wildlife gardens
- Low Maintenance
Pruning
Pests
May be susceptible to aphids, scale insects, pear blister mite, red spider mite and sawfly larvae
Diseases
May be susceptible to fireblight, apple canker, silver leaf and honey fungus
Get involved
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