Growli

Soil & potting mix

Best soil for Kohlrabi 'Winner' (Brassica oleracea var. gongylodes 'Winner')

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.

Preferred mix: Rich, moisture-retentive, well-drained loam, pH 6.0-7.5

Watch for — Cabbage root fly: Larvae tunnel the stem base and stunt or kill young plants. Fit brassica collars at the stem or net plants to block egg-laying females.

Why kohlrabi 'winner' needs this mix

Kohlrabi 'Winner' hates drying out, so it wants a mix that stays evenly moist — but it still needs perlite so "moist" never tips into "waterlogged".

For the full picture on what makes up a good mix, see our guide to the main types of soil and potting media — it explains why each ingredient above behaves the way it does.

What goes wrong with the wrong mix

The wrong soil is one of the most common reasons kohlrabi 'winner' struggles, and the damage often shows up weeks later as a watering problem. For this species specifically:

Using a sharp, fast-draining "houseplant" or cactus-leaning mix that lets kohlrabi 'winner' dry out. It needs a moisture-retentive but still airy blend.

pH — does it matter for kohlrabi 'winner'?

Kohlrabi 'Winner' prefers a slightly acidic mix (around pH 5.5-6.5); a peat-free compost-and-coir blend sits there naturally, so routine pH testing is unnecessary.

If you want to check or adjust it, the soil pH guide walks through testing and the safe ways to nudge a mix more acidic or more alkaline.

DIY mix vs a bagged one

A good peat-free houseplant compost works for kohlrabi 'winner' straight from the bag if you mix in some perlite for air. The DIY ratio above gives a more reliable moisture-to-air balance.

Drainage and the pot

Use a pot with a drainage hole but a less-porous material (plastic or glazed) so it does not dry too fast. Bottom-watering keeps the mix evenly moist without sogging the crown.

Peat-free mixes slump and compact as they hold moisture, so refresh kohlrabi 'winner''s mix every 12-18 months to keep air in the rootball even if the pot size is unchanged. When the time comes, our repotting guide for kohlrabi 'winner' covers the timing and technique step by step.

Kohlrabi 'Winner' soil — frequently asked questions

What is the best soil mix for kohlrabi 'winner'?

3 parts peat-free houseplant compost : 1 part coco coir : 1 part perlite. Kohlrabi 'Winner' comes from damp, shaded forest floors and has fine roots that scorch and brown the moment the rootball dries — the mix has to hold a steady reserve.

Can I use normal potting soil for kohlrabi 'winner'?

A free-draining, gritty mix dries too fast for kohlrabi 'winner' — you get crispy brown edges and frond or leaf drop within days of one missed watering. A good peat-free houseplant compost works for kohlrabi 'winner' straight from the bag if you mix in some perlite for air. The DIY ratio above gives a more reliable moisture-to-air balance.

Does kohlrabi 'winner' need a special pH?

Kohlrabi 'Winner' prefers a slightly acidic mix (around pH 5.5-6.5); a peat-free compost-and-coir blend sits there naturally, so routine pH testing is unnecessary.

Should I buy a bagged mix or make my own for kohlrabi 'winner'?

A good peat-free houseplant compost works for kohlrabi 'winner' straight from the bag if you mix in some perlite for air. The DIY ratio above gives a more reliable moisture-to-air balance.

How often should I refresh the soil for kohlrabi 'winner'?

Peat-free mixes slump and compact as they hold moisture, so refresh kohlrabi 'winner''s mix every 12-18 months to keep air in the rootball even if the pot size is unchanged. Use a pot with a drainage hole but a less-porous material (plastic or glazed) so it does not dry too fast. Bottom-watering keeps the mix evenly moist without sogging the crown.

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