Allium 'Haarlem Superglobe'
Hybrid group of perennial, bulbous plants, producing densely-packed spherical heads of star-shaped flowers, in shades of pink, purple or white, on straight stems to 70cm tall in May and June, above short-lived, mid-green leaves. The foliage is often wilting and turning brown when the flowers appear, and for best visual effect, the bulbs should be sited so that adjacent plants can grow to conceal the leaves as they die back. The flowers are extremely attractive to bees and other pollinating insects, making the plant a wonderful addition to a wildlife garden.
Size
Ultimate height
0.5–1 metresTime to ultimate height
1–2 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Moist but well–drained, Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Pink Purple White | Green | ||
|---|---|---|---|---|
| Summer | Pink Purple White | Green | ||
| Autumn | ||||
| Winter |
Position
- Full sun
Aspect
South–facing or West–facing
Exposure
Sheltered Hardiness
H5Botanical details
- Family
- Amaryllidaceae
- Native to the UK
- No
- Foliage
- Deciduous
- Habit
- Clump forming
- Genus
Allium are bulbous herbaceous perennials with a strong onion or garlic scent, linear, strap-shaped or cylindrical basal leaves and star-shaped or bell-shaped flowers in an umbel on a leafless stem
- Name status
Unresolved
How to grow
Cultivation
Easy to grow in full sun and a fertile well-drained soil. It is best to grow in containers where garden soil is heavy clay and prone to saturation over winter. See allium cultivation
Propagation
Propagate by offsets to obtain plants the same as the mother bulb, which can be carefully detached by lifting the bulb after flowering has finished. See bulb propagation. Propagation by seed may not produce plants that are true, as this is a hybrid plant
Suggested planting locations and garden types
- Cottage and informal garden
- Patio and container plants
- Wildlife gardens
- City and courtyard gardens
- Cut flowers
- Flower borders and beds
Pruning
No pruning required, other than to remove old flowered stems and foliage
Pests
May be susceptible to slugs, snails and allium leaf miner
Diseases
May be susceptible to onion white rot, and onion downy mildew
Get involved
The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.