Kohlrabi, often called the “German turnip,” is a unique and versatile vegetable prized for its crisp, mildly sweet, and slightly peppery taste. Resembling a turnip with its bulbous stem and leafy greens, kohlrabi is rich in vitamins C and B6, potassium, and fiber, making it an excellent addition to a healthy diet. Despite its unusual appearance, growing kohlrabi at home is surprisingly easy and highly rewarding. With the right techniques, gardeners of all experience levels can produce abundant, healthy bulbs and leaves right in their backyard or balcony. This guide reveals the secrets to successful kohlrabi cultivation.
Why Grow Kohlrabi at Home?
Homegrown kohlrabi offers several advantages:
- Freshness and flavor: Freshly harvested kohlrabi is sweeter and more tender than store-bought varieties.
- Health benefits: Packed with antioxidants, vitamins, and fiber, it supports immunity, digestion, and overall wellness.
- Space efficiency: Kohlrabi grows well in garden beds, raised containers, or even large pots, making it ideal for small spaces.
- Multiple uses: Both the bulb and the leaves are edible; bulbs can be roasted, steamed, or eaten raw, while leaves can be sautéed or added to soups.
- Quick harvest: Early varieties can be harvested in as little as 45–60 days.
With its ease of growth and nutritional value, kohlrabi is perfect for home gardeners looking to diversify their vegetable garden.
Choosing the Right Kohlrabi Variety
Kohlrabi varieties differ in size, color, and maturity period. Selecting the right type depends on your climate and space:
- Early varieties: Mature in 45–60 days, producing small, tender bulbs. Examples include ‘Grand Duke’ and ‘Kolibri’.
- Main-season varieties: Take 60–80 days to mature but produce larger bulbs suitable for storage. Examples include ‘Purple Vienna’ and ‘White Vienna’.
- Color selection: Kohlrabi bulbs come in green and purple. The taste is similar, but purple varieties can add color to your garden and dishes.
Choose certified seeds or healthy seedlings from a trusted source to ensure strong growth and disease resistance.
Soil Preparation for Kohlrabi
Healthy soil is the foundation for high-yielding kohlrabi. Key soil requirements include:
- Soil type: Well-drained, loamy soil with good organic matter content. Avoid heavy clay, which can cause bulbs to split.
- pH range: Slightly acidic to neutral (6.0–7.0) is ideal.
- Fertility: Kohlrabi is a nutrient-demanding crop. Incorporate compost or well-rotted manure to boost soil fertility.
To prepare the soil:
- Clear the bed of weeds and debris.
- Loosen the soil to a depth of 8–10 inches to allow proper root and bulb expansion.
- Mix in compost or organic fertilizer to promote early growth and bulb development.
Proper soil preparation ensures strong stems, healthy leaves, and tender bulbs.
Sowing Seeds and Transplanting
Kohlrabi can be started from seeds or seedlings. Here’s the process for home cultivation:
Step 1: Seed Sowing
- Sow seeds ½ inch deep in seed trays, small pots, or directly in prepared garden beds.
- Space seeds 1–2 inches apart and water gently to keep the soil consistently moist.
- Seeds germinate in 7–10 days under optimal conditions (cool to moderate temperatures, 50–75°F).
Step 2: Thinning
- When seedlings develop 2–3 true leaves, thin them to 4–6 inches apart to avoid overcrowding. Proper spacing allows bulbs to grow evenly and reduces disease risk.
Step 3: Transplanting
- If started in trays or pots, transplant seedlings to the garden when they are 3–4 weeks old and have strong roots.
- Space rows 12–18 inches apart to allow airflow and easy access for maintenance.
Transplanting at the right stage ensures minimal stress and faster establishment in the garden.
Optimal Growing Conditions
Kohlrabi is a cool-season crop that thrives under the following conditions:
- Temperature: 55–75°F is ideal. Excessive heat can cause the bulbs to become woody and bitter.
- Sunlight: Full sun for at least 6 hours daily encourages strong growth and bulb development.
- Moisture: Keep the soil evenly moist. Irregular watering can result in cracked or tough bulbs.
- Fertilization: A balanced fertilizer with nitrogen, phosphorus, and potassium supports leafy growth and bulb formation.
Maintaining these conditions ensures uniform, tender, and flavorful kohlrabi bulbs.
Caring for Kohlrabi
Regular care is key to achieving maximum yields. Here are expert practices:
Watering
- Water consistently, especially during bulb enlargement.
- Avoid waterlogging, which can lead to root rot or fungal diseases.
- Mulching helps retain moisture and suppress weeds.
Fertilization
- Apply nitrogen during early growth to encourage leafy stems.
- Switch to phosphorus and potassium as bulbs begin to form to promote size and firmness.
- Organic options, such as compost tea or worm castings, support soil health.
Pest and Disease Management
Common pests include aphids, cabbage worms, flea beetles, and leaf miners. Control strategies:
- Handpick pests or use organic sprays like neem oil.
- Maintain proper spacing and remove affected leaves to reduce disease spread.
- Rotate crops to prevent soil-borne diseases like clubroot and downy mildew.
Early detection and preventive care prevent yield loss and maintain plant vigor.
Thinning and Pruning
- Remove weak or damaged seedlings to allow strong plants more space.
- Occasionally remove older outer leaves to improve airflow and sunlight penetration.
- Avoid excessive pruning, as leaves are essential for photosynthesis and bulb growth.
Harvesting Kohlrabi
Kohlrabi matures quickly compared to many other vegetables. Key harvesting tips:
- Timing: Harvest bulbs when they are 2–3 inches in diameter. Larger bulbs may become woody and lose tenderness.
- Method: Gently pull the bulb from the soil, taking care not to damage surrounding plants.
- Leaves: Remove healthy outer leaves for use in cooking without compromising bulb growth.
Regular harvesting encourages new bulb development and prolongs the harvest season.
Maximizing Yield in Small Spaces
Kohlrabi is ideal for small-space gardening due to its compact growth habit. Strategies to increase yield include:
- Succession planting: Sow new seeds every 2–3 weeks to ensure a continuous harvest.
- Vertical planting: Use raised beds or containers with proper spacing to maximize terrace or balcony space.
- Intercropping: Plant kohlrabi with quick-growing crops like radishes or spinach to optimize garden space.
Even in limited areas, these techniques allow gardeners to enjoy multiple harvests and abundant produce.
Storage and Use
Kohlrabi can be stored and used in multiple ways:
- Short-term storage: Keep unwashed bulbs in a cool, dark place for up to 2 weeks.
- Long-term storage: Refrigerate bulbs in perforated plastic bags to maintain moisture for up to a month.
- Cooking and eating: Slice raw for salads, roast, steam, or add to soups and stir-fries. Leaves can also be sautéed like spinach.
Proper storage and use reduce waste and ensure maximum nutritional benefit.
Common Mistakes to Avoid
Even experienced gardeners can make mistakes with kohlrabi. Avoid these common pitfalls:
- Overcrowding: Leads to small, misshapen bulbs.
- Irregular watering: Causes cracking or tough bulbs.
- Planting in hot weather: Heat can trigger bolting and bitter taste.
- Neglecting pest control: Aphids, flea beetles, and caterpillars can devastate crops quickly.
- Harvesting too late: Bulbs become woody and unpalatable if left in the soil too long.
Awareness of these mistakes allows gardeners to correct course and ensure a bountiful harvest.
Conclusion
Growing kohlrabi at home is easier than many people think and incredibly rewarding. By selecting the right variety, preparing fertile soil, maintaining proper spacing, and providing consistent care, you can enjoy abundant, healthy bulbs and leafy greens in your garden or terrace. Kohlrabi’s quick growth, nutritional value, and versatility make it an ideal choice for urban gardeners and home cooks alike.
Following these expert tips—proper soil preparation, watering, fertilization, pest management, and timely harvesting—you can transform a small garden space into a productive, continuous source of fresh, flavorful kohlrabi. Whether eaten raw, roasted, or sautéed, your homegrown kohlrabi will be a nutritious and satisfying addition to meals all season long.
Growing kohlrabi is not only about harvesting food; it’s about cultivating healthy habits, sustainability, and the joy of producing your own fresh vegetables. With careful attention and consistent care, your home garden can yield bountiful kohlrabi harvests year after year.