Kohlrabi reaches harvest size approximately eight weeks after planting seeds. This quick-growing vegetable is a favorite for gardeners who want fast results, and understanding exactly how long does kohlrabi take to grow helps you plan your garden schedule perfectly.
Whether you are a beginner or an experienced grower, kohlrabi offers a crisp, mild flavor that resembles broccoli stems or cabbage hearts. The key is knowing the timeline from seed to harvest so you can pick it at its peak tenderness.
How Long Does Kohlrabi Take To Grow
From sowing seeds to harvesting mature bulbs, kohlrabi typically takes 45 to 60 days. Some varieties mature faster, while others need a bit more time. The exact duration depends on the cultivar, weather conditions, and soil quality.
Here is a breakdown of the growth stages:
- Seed germination: 5 to 10 days
- Seedling stage: 10 to 14 days after sprouting
- Bulb formation: 20 to 30 days after transplanting or thinning
- Harvest readiness: 45 to 60 days from seed
Most gardeners harvest kohlrabi when the bulb is 2 to 3 inches in diameter. If you wait too long, the flesh becomes woody and less flavorful.
Factors That Affect Growth Time
Several elements influence how quickly kohlrabi reaches maturity. Paying attention to these can speed up or slow down your harvest.
Temperature And Season
Kohlrabi grows best in cool weather. Ideal temperatures are between 60°F and 70°F. In hot conditions, the plant may bolt or produce tough bulbs. In cold weather, growth slows down but the flavor often improves.
Plant kohlrabi in early spring for a summer harvest, or in late summer for a fall crop. Avoid planting during peak heat.
Soil Quality And Moisture
Rich, well-draining soil with plenty of organic matter helps kohlrabi grow faster. The soil pH should be between 6.0 and 7.5. Consistent moisture is critical; dry soil causes the bulb to become tough and stringy.
Water deeply once or twice a week, especially during dry spells. Mulching around the plants retains moisture and keeps the roots cool.
Variety Selection
Different kohlrabi varieties have different maturity times. Some are ready in as little as 40 days, while others take up to 70 days. Check the seed packet for the specific days to maturity.
Popular fast-maturing varieties include:
- Early White Vienna: 50 to 55 days
- Kolibri: 45 to 50 days
- Korridor: 40 to 45 days
- Superschmelz: 60 to 70 days (slower but larger)
Choose a variety that matches your climate and desired harvest window.
Step-By-Step Growing Guide
Follow these steps to ensure your kohlrabi grows on schedule and reaches harvest size quickly.
1. Prepare The Soil
Loosen the soil to a depth of 8 to 10 inches. Mix in compost or aged manure to improve fertility. Remove rocks and debris that could hinder root growth.
Kohlrabi prefers a sunny spot with at least 6 hours of direct sunlight daily. Partial shade is okay but may slow growth.
2. Sow Seeds Directly Or Start Indoors
You can sow kohlrabi seeds directly in the garden or start them indoors for an earlier harvest. Direct sowing is simpler and works well for most gardeners.
Plant seeds ¼ to ½ inch deep, spaced 1 inch apart. Thin seedlings to 4 to 6 inches apart once they have two true leaves. If starting indoors, transplant seedlings when they are 3 to 4 weeks old.
3. Water Consistently
Keep the soil evenly moist but not waterlogged. Inconsistent watering leads to cracked or tough bulbs. Use a soaker hose or drip irrigation to maintain steady moisture.
Check soil moisture by sticking your finger an inch into the ground. If it feels dry, it is time to water.
4. Fertilize Lightly
Kohlrabi is a light feeder. Apply a balanced fertilizer (10-10-10) at planting time. Side-dress with compost or a nitrogen-rich fertilizer when the bulbs start to swell.
Avoid over-fertilizing, which can cause lush leaves but small bulbs.
5. Monitor For Pests And Diseases
Common pests include aphids, cabbage worms, and flea beetles. Use row covers to protect young plants. Handpick larger pests or apply insecticidal soap if needed.
Rotate crops each year to prevent soil-borne diseases like clubroot. Keep the garden clean and remove plant debris after harvest.
When To Harvest Kohlrabi
Harvesting at the right time ensures the best texture and flavor. The bulb should be firm and about 2 to 3 inches across. Leaves should still be green and healthy.
If the bulb starts to crack or the skin becomes tough, you waited too long. Cut the stem at ground level with a sharp knife. Remove the leaves and store the bulb in the refrigerator.
You can eat the leaves too; they are nutritious and taste similar to kale or collards.
Tips For Faster Growth
If you want to speed up the process, try these strategies:
- Use transplants instead of direct seeds to save 1 to 2 weeks
- Plant in raised beds for warmer soil
- Apply a liquid seaweed fertilizer every 2 weeks
- Keep soil temperature above 50°F for optimal germination
- Thin seedlings promptly to reduce competition
These methods can shave several days off the total growth time.
Common Mistakes That Slow Growth
Avoid these errors to keep your kohlrabi on track:
- Planting too deep: Seeds need light to germinate; plant shallowly.
- Overcrowding: Thin seedlings to give each plant enough space.
- Inconsistent watering: Leads to stress and slow bulb development.
- Planting in hot weather: Causes bolting and poor quality.
- Ignoring pests: Aphids and worms can stunt growth significantly.
By avoiding these pitfalls, you can harvest kohlrabi closer to the minimum time frame.
Growing Kohlrabi In Containers
If you have limited space, kohlrabi grows well in containers. Use a pot at least 8 inches deep with drainage holes. Fill with high-quality potting mix.
Plant one kohlrabi per 6-inch pot, or space them 4 inches apart in larger containers. Water more frequently because containers dry out faster. Fertilize every 2 weeks with a diluted liquid fertilizer.
Container-grown kohlrabi may mature slightly slower than in-ground plants, but you can still expect harvest within 50 to 60 days.
Succession Planting For Continuous Harvest
To enjoy kohlrabi all season, plant a new batch every 2 to 3 weeks. This ensures a steady supply of tender bulbs. Stop planting 4 to 6 weeks before your first expected frost for fall crops.
Succession planting works best with fast-maturing varieties. Keep a garden journal to track planting dates and harvest times.
Storing And Using Kohlrabi
After harvesting, remove the leaves and store the bulbs in a plastic bag in the refrigerator. They stay fresh for 2 to 3 weeks. The leaves can be stored separately for up to a week.
Kohlrabi can be eaten raw, roasted, steamed, or added to soups and stir-fries. Peel the tough outer skin before eating. The flesh is crunchy and slightly sweet.
For long-term storage, blanch and freeze kohlrabi cubes. They retain texture well for several months.
Frequently Asked Questions
How Long Does Kohlrabi Take To Grow From Seed?
From seed to harvest, kohlrabi takes about 45 to 60 days. Some early varieties are ready in 40 days, while larger types may need up to 70 days.
Can Kohlrabi Be Grown In Hot Weather?
Kohlrabi prefers cool weather. High temperatures can cause the bulbs to become tough or the plant to bolt. Plant in spring or fall for best results.
How Do I Know When Kohlrabi Is Ready To Pick?
Harvest when the bulb is 2 to 3 inches in diameter and feels firm. If the skin starts to crack or the bulb feels soft, it is past its prime.
Does Kohlrabi Need Full Sun?
Yes, kohlrabi grows best in full sun with at least 6 hours of direct sunlight daily. Partial shade is acceptable but may slow growth.
Can I Eat Kohlrabi Leaves?
Yes, kohlrabi leaves are edible and nutritious. They taste similar to kale or collard greens and can be cooked or used in salads.
Final Thoughts On Kohlrabi Growth Time
Knowing how long does kohlrabi take to grow helps you plan your garden and avoid disappointment. With proper care, you can enjoy fresh, crunchy bulbs in under two months.
Start with a fast-maturing variety, keep the soil moist, and harvest at the right size. Your patience will be rewarded with a delicious crop that is easy to grow and versatile in the kitchen.
Whether you are a seasoned gardener or trying kohlrabi for the first time, this vegetable is a reliable choice for quick, satisfying results. Plant it now and watch it grow faster than you expect.