Allium hollandicum
Allium hollandicum
Dutch allium bears large purple-lilac globes 10cm across on stiff upright stems in late spring. Very similar to Purple Sensation but the species form is slightly taller with more open flower heads. Reliable and long-lived in UK borders. Excellent for cutting and drying. Naturalises well in sunny borders.
Where to plant
Best aspect
Border position
When to plant and expect flowers
Plant
Flowers
How to grow allium hollandicum
Plant 10-15cm deep in autumn. One of the most reliable tall alliums for UK conditions. Naturalises well in free-draining soil. Leave seed heads standing through winter for structural interest and self-seeding.
Soil requirements
Soil type
loam, sand, chalk
Moisture
well drained
pH
neutral, alkaline
Aftercare
Allow foliage to die back naturally after flowering. Remove spent flower heads to prevent self-seeding.
Propagation
- Offsets in autumn
- Seed
Wildlife value
Toxicity
All parts mildly toxic. Contains organosulfur compounds causing gastrointestinal upset.
Common problems
- Slugs and snails
- Squirrels digging up bulbs
Similar bulbs to grow
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