Brassica oleracea var. gongylodes

Kohlrabi Growing & Harvesting Guide

Kohlrabi (Brassica oleracea var. gongylodes), the sweet and crispy 'turnip-cabbage' of cool-season plots, is a highly rewarding crop. Prized for its round swollen stem bulb sitting upon the soil line, this resilient brassica demands highly fertile loam, even watering, and cool frost ripening.

Sunlight Full Sun (6+ hours)

Watering Moderate / Consistent

Soil pH Rich, Free-Draining, Humus Loam (pH 6.0-7.0)

Target Temp 12°C - 24°C

Toxicity Pet Friendly (Non-toxic)

Botanical macro photography of Kohlrabi (Brassica oleracea var. gongylodes) - Plant AI care database

How to Identify Kohlrabi

Kohlrabi (Brassica oleracea var. gongylodes) is a highly valued edible crop globally. Recognizing its definitive vegetative and fruit/vegetable structures is key to successful companion growing and harvesting.

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Key Visual Features: Low-growing biennial cole crop with blue-green leaves on long stalks.
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Leaf & Stems: Large leaves rise directly from a round swollen stem bulb sitting just above the soil.
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Fruit/Edible Part: Swollen globose light-green or purple stem bulb with a crispy, sweet turnip-like flesh.

💡 Plant AI Tip: Snap a photo with Plant AI to identify garden veggies and diagnose leaf spot diseases instantly.

Complete Growing & Harvesting Guide

Follow our detailed scientific agricultural cultivation guide to keep your Kohlrabi thriving and high-yielding.

Water consistently, providing 1 inch of water weekly. Maintain steady soil moisture; dry spells cause tough woody bulbs.

No pruning required. Simply remove yellowing lower leaves that rest on the soil to prevent disease.

Moderate feeder. Apply rich organic compost at planting and side-dress with fish emulsion every 4 weeks.

Requires full sun (6+ hours daily) to develop robust leaves and swell the crispy stem bulb.

Prefers loose, fertile, well-draining loamy soil enriched with organic compost (pH 6.0-7.0).

Sow seeds 0.25 inch deep directly outdoors in early spring, or late summer for a sweet autumn crop.

Cool-season crop. Best growth occurs between 12°C and 24°C; tolerates light frost which makes the bulbs taste sweeter.

Space plants 6 inches apart in rows spaced 12 inches apart to allow sufficient bulb swelling room.

Prone to cabbage worms, flea beetles, and aphids. Use protective fine mesh row covers early in spring.

Susceptible to Black Rot and Clubroot. Avoid waterlogging and rotate brassica crops every 3 years.

Harvest when the swollen stem bulb is between 2 and 3 inches in diameter. Cut the bulb at the soil line.

Common Diseases & Treatment

Kohlrabi Black Rot (Xanthomonas)

Symptoms: Leaves develop V-shaped yellow spots along leaf margins; veins inside leaf stems turn black and rot.

Action: Use certified disease-free seeds, avoid overhead watering, and discard infected plants immediately.

Clubroot (Plasmodiophora)

Symptoms: Plant leaves wilt during warm afternoons; subterranean roots develop massive, distorted swollen galls.

Action: Practice 4-year brassica crop rotation, raise soil pH to 7.2 using agricultural lime, and ensure sharp soil drainage.

Frequently Asked Questions

Why is my kohlrabi bulb tough, woody, and stringy?

This is caused by letting the bulb grow too large (over 3 inches) or exposing the plant to dry spells, which triggers tough wood fiber development.

Can I eat the leaves of the kohlrabi plant?

Yes! Kohlrabi leaves are highly nutritious and delicious. Cook them just like kale, collard greens, or spinach.

When should I plant kohlrabi for the best flavor?

Kohlrabi tastes best when grown in cool weather. Plant in early spring for a summer crop, or late summer to harvest sweet bulbs after autumn frosts.

Is kohlrabi safe for cats and dogs?

Yes! Plain, cooked or raw kohlrabi bulb is completely non-toxic and safe for dogs and cats. (Feed in small amounts to prevent gas).