Allium atropurpureum

RHS Plant Profile
very-dark purple allium

Synonyms

Allium nigrum var. purpureum

Plants for pollinators
Bulbs

A hardy perennial bulb, up to 60cm tall, with strap-shaped green leaves. Deep purple-red flowers, packed into a half-sphere shape up to 5cm across, are borne on upright stems in late spring and early summer

Position

Full sun

Soil Types

Chalk, Clay, Loam, Sand

Max Height

0.5-1 metres

Max Spread

0.1-0.5 metres

Size

Time to Maturity
2–5 years
Max Spread
0.1-0.5 metres
Max Height
0.5-1 metres

Growing Conditions

Chalk Clay Loam Sand
Moisture
Moist but well–drained or Well–drained
pH
Acid or Alkaline or Neutral

Position

Full sun
Aspect
South–facing or West–facing or East–facing
Exposure
Sheltered
Hardiness
H5

Colour & Scent

Fragrance Foliage
Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Amaryllidaceae
Native to GB/Ireland
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
Correct
Plant Range
Hungary to Turkey

How to Grow

Cultivation

Easy to grow in fertile well-drained soil. Add grit when grown in clay soils to improve drainage. See allium cultivation

Propagation

Propagate by seed, sowing in containers in a cold frame when just ripe or in the spring. Alternatively, remove offsets in autumn

Suggested planting locations and garden types

  • Architectural
  • Cottage and informal garden
  • Gravel garden
  • City and courtyard gardens
  • Wildlife gardens
  • Cut flowers
  • Flower borders and beds

Pruning

No pruning required

Pests

Generally pest-free

Diseases

May be susceptible to onion white rot and downy mildews