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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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Ultimate height

0.1–0.5 metres

Time to ultimate height

1 year

Ultimate spread

0.1–0.5 metres

Chalk

Clay

Loam

Sand

Moisture

Moist but well–drained

pH

Alkaline, Neutral, Acid

	Stem	Flower	Foliage	Fruit
Spring
Summer
Autumn
Winter

Full sun

Aspect

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

Exposure

Exposed or 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)

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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