Troubleshooting
Kohlrabi problems — and how to fix them
Kohlrabi (Brassica oleracea var. gongylodes) is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Woody, split bulbs
Caused by drought, irregular watering or leaving bulbs too long. Keep moisture even and harvest young, ideally when the swollen stem is tennis-ball sized or smaller.
Flea beetles
Beetles riddle seedling leaves with small holes, checking growth. Cover with fine mesh, keep plants well watered, and sow into warm soil for fast establishment.
Cabbage root fly
Larvae feed on roots, wilting and stunting young plants. Fit brassica collars around stems at transplanting or use insect-proof mesh to block egg-laying.
Bolting
Cold checks to young plants or hot, dry spells can trigger premature flowering before the bulb forms. Sow into warm conditions and keep growth steady and unstressed.
Prevent kohlrabi problems before they start
Most kohlrabi issues are care-mismatch, not bad luck. Dial in the basics:
Looking for kohlrabi in general rather than its problems? Read the full kohlrabi care guide — light, water, soil and feeding.
Kohlrabi problems — FAQ
Why is my kohlrabi woody, split bulbs?
Caused by drought, irregular watering or leaving bulbs too long. Keep moisture even and harvest young, ideally when the swollen stem is tennis-ball sized or smaller.
Why is my kohlrabi flea beetles?
Beetles riddle seedling leaves with small holes, checking growth. Cover with fine mesh, keep plants well watered, and sow into warm soil for fast establishment.
Why is my kohlrabi cabbage root fly?
Larvae feed on roots, wilting and stunting young plants. Fit brassica collars around stems at transplanting or use insect-proof mesh to block egg-laying.
Why is my kohlrabi bolting?
Cold checks to young plants or hot, dry spells can trigger premature flowering before the bulb forms. Sow into warm conditions and keep growth steady and unstressed.