Fertilising guide

How to fertilise Kohlrabi 'Winner' (Brassica oleracea var. gongylodes 'Winner')— schedule & NPK

Also called Winner kohlrabi, white kohlrabi.

More about kohlrabi 'winner'

About Kohlrabi 'Winner'

Brassica oleracea var. gongylodes 'Winner' · also called Winner kohlrabi, white kohlrabi · edible

Kohlrabi 'Winner' is a reliable pale-green ('white') variety prized for smooth, uniform globes and sweet, crisp flesh in about 45-55 days. It resists splitting and stays tender over a longer harvest window than older strains. Like all kohlrabi it needs cool conditions, rich soil and steady water to size up without turning woody.

Growth habit: Compact rosette of upright blue-green leaves over a swollen, pale-green above-ground stem forming the edible globe.

Watch for — Flea beetles: Tiny beetles riddle young leaves with shot-holes, stunting seedlings. Use floating row cover at emergence and keep plants vigorous to grow through damage.

What fertiliser kohlrabi 'winner' actually wants — and why

Kohlrabi 'Winner' is grown entirely for its leaves, so nitrogen is the priority — steady, nitrogen-leaning feeding keeps it growing fast, tender and unbolted.

For the language behind the three numbers on the bottle — what nitrogen, phosphorus and potassium each do — see the NPK ratio explained entry. The short version for kohlrabi 'winner': match the feed to the job the plant is doing right now, not to a generic “plant food” on the shelf.

How often to feed kohlrabi 'winner', and which months

Feeding only earns its keep while the plant is in active growth and can use the nutrients — pour feed into a dormant or low-light plant and it simply builds up as root-burning salt. For kohlrabi 'winner':

Feed as a heavy feeder: rich base dressing of compost or balanced fertiliser, then one nitrogen side-dress about 3-4 weeks after planting to push leafy growth that fuels the bulb. In practice: a balanced or compost-rich start, then a nitrogen side-dress or liquid feed every 3-4 weeks through the cropping period in the main season (spring through early autumn).

The dormant-season rule matters more than the exact interval: skip feeding entirely when kohlrabi 'winner' is resting. For the wider context on indoor feeding rhythms across the seasons, the houseplant fertiliser schedule walks through the year month by month.

What strength to mix for kohlrabi 'winner'

Use the vegetable-feed label rate for kohlrabi 'winner'. Steady availability matters more than a strong dose — a check in growth makes leaves tough and can trigger bolting.

Feeding always goes onto already-damp soil, never dry roots — water kohlrabi 'winner' first if the soil is dry, then apply the diluted feed. The companion question is when to water at all, covered in the kohlrabi 'winner' watering schedule.

Signs you are over-feeding kohlrabi 'winner'

Over-feeding is far more common — and more damaging — than under-feeding for most plants. The classic tells for kohlrabi 'winner':

Very soft, floppy, dark-green growth that attracts aphids.
Excess leafy growth at the expense of hearts/heads in cabbage and the like.
Salt crust and scorched leaf edges in containers; nitrate-heavy leaves.

Signs you are under-feeding kohlrabi 'winner'

Pale, yellow-green leaves, oldest first, and slow growth.
Small, tough, bitter leaves and premature bolting.
Weak, stunted heads in cabbage, broccoli and cauliflower.

If the symptoms point at watering, light or roots rather than nutrition, the full kohlrabi 'winner' care brief covers soil, humidity and the common problems for this species.

Flushing and leaching the salts

For container-grown kohlrabi 'winner', water until it drains freely each time and flush pots monthly with plain water to stop nitrogen salts accumulating; in the ground, good compost levels naturally buffer this.

Organic vs synthetic feeds for kohlrabi 'winner'

Organic options

Well-rotted manure or compost dug in, plus nitrogen-rich liquid feeds like diluted chicken-manure pellets or nettle feed. UK: pelleted chicken manure or Westland; US: Espoma Garden-tone or blood meal. Steady and soil-building.

Synthetic / liquid feeds

A balanced feed at planting then a high-nitrogen liquid or granular side-dress — UK: Growmore then a nitrogen feed or Phostrogen; US: a 10-10-10 then a high-N (e.g. 21-0-0) side-dress or Miracle-Gro.

Brand names are examples, not endorsements, and UK and US ranges differ — check the label’s own NPK and dilution rate, since formulations change.

Fertilising kohlrabi 'winner' — frequently asked questions

What fertiliser does kohlrabi 'winner' need?

A nitrogen-leaning feed (higher first number) or compost-rich soil — nitrogen drives the fast, tender leafy growth this crop is grown for. Phosphorus and potassium matter far less here than for fruiting crops. Kohlrabi 'Winner' is grown entirely for its leaves, so nitrogen is the priority — steady, nitrogen-leaning feeding keeps it growing fast, tender and unbolted.

How often should I feed kohlrabi 'winner'?

Feed as a heavy feeder: rich base dressing of compost or balanced fertiliser, then one nitrogen side-dress about 3-4 weeks after planting to push leafy growth that fuels the bulb. Feed as a heavy feeder: rich base dressing of compost or balanced fertiliser, then one nitrogen side-dress about 3-4 weeks after planting to push leafy growth that fuels the bulb. In practice: a balanced or compost-rich start, then a nitrogen side-dress or liquid feed every 3-4 weeks through the cropping period in the main season (spring through early autumn).

What strength of feed for kohlrabi 'winner'?