Juglans sigillata
iron walnut
A broad deciduous tree reaching 25m tall by 15m wide. The leaves emerge copper-coloured then become bright green then yellow before they fall. They are very large (up to 50cm long) and have usually 9 or 11 pointed leaflets which are fragranced when bruised. The flowers are insignificant but turn into green fruit in late summer from which edible walnuts can be extracted.
Size
Ultimate height
Higher than 12 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 | Green | Green Bronze | ||
|---|---|---|---|---|
| Summer | Green | |||
| Autumn | Yellow | Green | ||
| Winter |
Position
- Full sun
- Partial shade
Aspect
East–facing or North–facing or South–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H6Botanical details
- Family
- Juglandaceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Spreading branched
- Genus
Juglans are deciduous trees with pinnate leaves, and inconspicuous flowers in catkins followed by usually edible nuts
- Name status
Correct
How to grow
Cultivation
Grow in any deep, fertile soil. Suited to very large gardens or parks. For nut production, more than one tree is needed for cross pollination
Propagation
Propagate by seed (for more advice see propagate from seed (tree/shrub)
Suggested planting locations and garden types
- Architectural
- Edible fruit
Pruning
Pests
May be susceptible to aphids and walnut blister mites
Diseases
May be susceptible to walnut leaf spot, walnut leaf blotch, honey fungus and coral spot
Get involved
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