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Annual Biennial

Brassica oleracea (Gongylodes Group) 'Kossak'

A large, fast-growing white kohlrabi with a mild taste, ready to eat in three months

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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
Chalk
Clay
Loam
Sand
Moisture
Moist but well–drained
pH
Alkaline, Neutral, Acid
Colour & scent
StemFlowerFoliageFruit
Spring Green
Summer White Green
Autumn White Green
Winter
Position
  • Full sun
Aspect

East–facing or North–facing or South–facing or West–facing

Exposure
Exposed or Sheltered
Hardiness
H5
Botanical details
Family
Brassicaceae
Native to GB / Ireland
No
Foliage
Evergreen
Habit
Tufted
Genus

Brassicas can be annual, biennial or perennial plants, most are upright with alternate, often glaucous leaves, long taproots and clusters of cross-shaped, yellow or white flowers. The genus includes a number of species bred to produce food crops, such as cabbages, turnips, mustards and oilseed rape, as well as others grown for their ornamental value

Name status

Accepted

How to grow

Cultivation

Grow in full sun in firm, fertile soil - including coastal regions

Propagation

Propagate by seed. See sowing vegetable seeds

Suggested planting locations and garden types
Pruning

No pruning required

Pests

May be susceptible to flea beetle when young, caterpillars of small white butterflies, cabbage root fly and mealy cabbage aphid. Also to pigeons

Diseases

May be susceptible to brassica downy mildew and brassica white blister. In areas where brassicas have been grown before, club root can build up in the soil

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