Magnolia sieboldii 'Colossus'
magnolia 'Colossus'
A large, deciduous shrub or spreading, small tree to 8m tall, the dark green leaves are up to 30cm long and 15cm wide, and the flowers, up to 15cm across, appear in late spring and early into midsummer. These are strongly scented, bowl-shaped, with 10-15 white petals and a large boss of deep red stamens in the centre. Ornamental fruits turn pink in autumn
Size
Ultimate height
4–8 metresTime to ultimate height
20–50 yearsUltimate spread
Wider than 8 metresGrowing conditions
Moisture
Moist but well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Red White | Green | ||
|---|---|---|---|---|
| Summer | Red White | Green | ||
| Autumn | Green | Red Pink | ||
| Winter |
Position
- Full sun
- Partial shade
Aspect
South–facing or West–facing or East–facing
Exposure
Sheltered Hardiness
H6Botanical details
- Family
- Magnoliaceae
- Native to the UK
- No
- Foliage
- Deciduous
- Habit
- Bushy
- Genus
Magnolia can be deciduous or evergreen trees or shrubs, with large, showy, often fragrant flowers, often opening before the leaves, and sometimes followed by colourful cone-like fruit
- Name status
Accepted
How to grow
Cultivation
Grow in moist but well drained neutral to acid soil in full sun or light shade with shelter from cold winds. Will grow in moist alkaline soils. Late frost may damage the flower buds. For more information see magnolia cultivation advice
Propagation
Propagate by softwood cuttings from late spring to early summer, or semi-ripe cuttings from late summer to autumn
Suggested planting locations and garden types
- City and courtyard gardens
- Architectural
- Cottage and informal garden
- Low Maintenance
- Wall side borders
Pruning
Magnolia pruning should be carried out in midsummer when in full leaf
Pests
May be susceptible to scale insects, horse chestnut scale and capsid bug
Diseases
May be susceptible to coral spot, phytophthora, grey moulds, honey fungus, a virus or fungal leaf spot
Get involved
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