Allium cepa (Aggregatum Group) 'Prisma'

RHS Plant Profile
shallot 'Prisma'

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shallot 'Prisma' visionspictures.com
Herbs - Culinary Bulbs

This shallot produces a cluster of larger than average bulbs with a red-brown skin and white flesh, which are said to store very well

Position

Full sun

Soil Types

Chalk, Loam, Sand

Max Height

0.1-0.5 metres

Max Spread

0.1-0.5 metres

Size

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

Growing Conditions

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

Position

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

Hardiness Ratings

All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets

  • H1A: under glass all year (>15C)
  • H1B: can be grown outside in the summer (10 - 15)
  • H1C: can be grown outside in the summer (5 - 10)
  • H2: tolerant of low temperatures, but not surviving being frozen (1 to 5)
  • H3: hardy in coastal and relatively mild parts of the UK (-5 to 1)
  • H4: hardy through most of the UK (-10 to -5)
  • H5: hardy in most places throughout the UK even in severe winters (-15 to -10)
  • H6: hardy in all of UK and northern Europe (-20 to -15)
  • H7: hardy in the severest European continental climates (< -20)
H6

Colour & Scent

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
Unresolved

How to Grow

Cultivation

Grow in any soil in full sun. They need moisture whilst growing but by July need very little. For more advice see how to grow: shallots

Propagation

Propagate by seed. See sowing vegetable seeds

Pruning

No pruning required

Pests

May be susceptible to birds pulling them out the ground, if they are planted as sets

Diseases

May be susceptible to onion downy mildew , onion white rot and leek rust