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Herbs - CulinaryBulbs

Allium cepa 'Mammoth Red'

onion 'Mammoth Red'

A very large, red skinned, exhibition quality onion with a strong, sweet flavour. Stores well

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Size
Ultimate height
0.1–0.5 metres
Time to ultimate height
1 year
Ultimate spread
0.1–0.5 metres
Growing conditions
Clay
Loam
Sand
Chalk
Moisture
Moist but well–drained
pH
Alkaline, Neutral
Colour & scent
StemFlowerFoliageFruit
Spring Green
Summer Green Red
Autumn
Winter
Position
  • Full sun
Aspect

South–facing or West–facing

Exposure
Sheltered
Hardiness
H3
Botanical 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

Accepted

How to grow

Cultivation

Grow in fertile, moisture retentive, but well-drained soil in full sun. Consider liming if the soil is acid, pH below 6.5. Yellowing and toppling of the foliage is a sign that the onions are reaching maturity. Lift and store in a cool dry place See How to grow: onions for further advice

Propagation

Propagate by seed. See sowing vegetable seeds

Suggested planting locations and garden types
Pruning

Not required

Pests

May be susceptible to onion fly, leek moth and narcissus eelworm

Diseases

May be susceptible to onion white rot, onion downy mildew, leek rust and onion neck rot. Bolting, producing flowers, may be a problem

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