🥦 Kohlrabi

Brassica oleracea var. gongylodes

vegetables brassica (stem vegetable, cole crop)

☀️ Sun

Full sun (6, 8 hours); tolerates partial shade better than most brassicas

💧 Water

Medium; 1 inch per week consistently; fluctuating water causes woody/tough bulbs; even moisture throughout bulb development essential for tenderness

🗺️ Zones

3, 4, 5, 6, 7, 8, 9, 10

🧪 Soil pH

6.0, 7.5 (slightly acidic to slightly alkaline)

🪴 Soil Type

Rich, well-drained loam with moderate organic matter; consistent fertility produces tender, non-woody bulbs; avoid excessive nitrogen (causes all leaves, small bulbs); boron is important for kohlrabi , deficiency causes hollow stem

🚿 Drainage

Well-drained; consistent moisture but not waterlogged

📏 Spacing

4, 6 inches apart for small bulbs; 8, 12 inches apart for large bulbs; rows 12, 18 inches; closer spacing produces smaller, more tender bulbs

⏱️ Maturity

45-60 days (from seed); harvest when stem swells to 2-3 inches diameter

🍴 Edible Parts

🍽️ Swollen stem (the 'bulb' , actually an enlarged stem, not root; eaten raw, roasted, steamed, mashed, in slaws) 🍽️ Leaves (edible , similar to kale/collards; cook like any brassica green) 🍽️ Stems/leaf ribs (tender when young) 🍽️ Peel (the fibrous skin , peel before eating mature bulbs; young bulbs may not need peeling)

Key:🤝 Grows well together❌ Keep apart☀️ Sun needs💧 Water🗺️ Hardiness zone

🤝 Companions (7)

🤝 Beet

Different plant parts harvested , beets are roots, kohlrabi is stem; complementary mineral usage; beets add minerals to soil that kohlrabi uses

🤝 Dill

Attracts beneficial wasps that parasitize cabbage worms; improves brassica growth and flavor

🤝 Lettuce

Lettuce is shallow-rooted and short-season, harvested before kohlrabi needs full space; lettuce grows in kohlrabi's light shade

🤝 Nasturtium

Trap crop for aphids and cabbage worms; repels various pests; ground cover retains moisture IMPORTANT management caveat: without active management, nasturtiums can become a SOURCE of aphids that migrate to nearby crops. Either remove aphid-infested nasturtium plants promptly, or treat the trap crop itself to eliminate the aphid colony before it spreads. Strategic placement within 4-5 feet of protected crops is key.

🤝 Onion/Garlic/Chives

Repels aphids, cabbage worms, and flea beetles from kohlrabi; allium's sulfur compounds mask brassica scent

🤝 Pea

Peas fix nitrogen; harvested by mid-season before kohlrabi matures (55, 70 days); complementary root depths

🤝 Sage/Rosemary

Aromatic oils repel cabbage moths and flea beetles; strong scent masks kohlrabi's host cues

⚠️ Keep Apart (4)

⚠️ Fennel

Allelopathic , severely inhibits kohlrabi growth

⚠️ Pole bean / Runner bean

Beans may be inhibited by brassica allelopathy; conflicting evidence but separation is conservative

⚠️ Strawberry

Brassicas and strawberries mutually inhibit growth; strawberries susceptible to verticillium wilt

⚠️ Tomato

Brassica root exudates may stunt tomato growth; separate by 3+ feet

💊 Medicinal Uses

Medicinal Properties

Excellent source of vitamin C , one cup provides 100%+ daily value; more vitamin C than oranges by weight
Contains glucosinolates and isothiocyanates , anti-cancer compounds (same as broccoli/kale)
Rich in fiber (both soluble and insoluble) , supports digestive health and satiety
Good source of vitamin B6, potassium, copper, and manganese
Contains lutein and zeaxanthin for eye health

📝 Growing Notes

Kohlrabi means 'cabbage turnip' in German, but it's a stem vegetable , the 'bulb' is an enlarged stem growing above ground, not a root. Two main types: green/white (most common, milder) and purple (more colorful, slightly spicier , both have white flesh inside). Kohlrabi is one of the fastest brassicas , harvest in 45, 60 days. HARVEST ON TIME , bulbs larger than 3, 4 inches become woody and fibrous. The key to tender kohlrabi: consistent water + harvest at golf-ball to tennis-ball size. Peeling is essential for mature bulbs , the skin is inedibly fibrous. Great for intercropping due to upright growth habit. Cabbage worms love kohlrabi leaves , Bt or row covers. Excellent spring and fall crop; bolts in heat above 80°F. Taste: mild, sweet, like a cross between broccoli stem and apple.

🛒 Buy Seeds & Plants

Baker Creek Heirloom Seeds Johnny's Selected Seeds Botanical Interests True Leaf Market Burpee Territorial Seed Company

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