Kohlrabi, a versatile and nutritious vegetable, can be preserved through canning for year-round enjoyment. This cabbage family member offers a unique flavor profile and impressive nutritional benefits. While canning kohlrabi is not typically recommended due to potential flavor changes and discoloration, it can be successfully preserved through pickling methods.
Pickling kohlrabi allows you to capture its crisp texture and mild, slightly sweet taste. The process involves peeling and slicing the kohlrabi, then soaking it in a brine solution before adding it to jars with a vinegar-based pickling liquid. This method not only preserves the vegetable but also enhances its flavor with aromatic spices and herbs.
Canned kohlrabi retains much of its nutritional value, including dietary fiber, vitamins, and minerals. It provides a good source of vitamin C, potassium, and calcium, while being low in calories. By canning kohlrabi at home, you can control the ingredients and avoid additives often found in store-bought versions.
Understanding Kohlrabi
Kohlrabi is a versatile and nutritious vegetable that belongs to the Brassica family. It features a unique bulb-like stem and edible leaves, offering a mild, sweet flavor.
Botanical Profile
Kohlrabi (Brassica oleracea var. gongylodes) is closely related to cabbage, broccoli, and kale. Its name comes from German, meaning “cabbage turnip.” The plant grows a swollen stem above ground, resembling a turnip.
Kohlrabi thrives in cool temperatures between 40°F and 75°F. It can withstand light frosts but may bolt if exposed to temperatures below 24°F. The plant prefers well-drained, fertile soil and moderate sunlight.
Varieties of Kohlrabi
Kohlrabi comes in several varieties, primarily differentiated by color and maturity rate. Common types include:
- White Vienna: Fast-growing with pale green skin
- Purple Vienna: Similar to White Vienna but with purple skin
- Early White Vienna: Matures quickly, ideal for short growing seasons
Some varieties are better suited for raw consumption, while others are preferable for cooking. Farmers and gardeners often choose based on climate and intended use.
Kohlrabi in the Kitchen
Kohlrabi is prized for its crunchy texture and mild, sweet flavor. The bulb can be eaten raw or cooked, while the leaves are edible and nutritious.
Raw kohlrabi is excellent in salads and slaws. It can be grated, sliced, or cut into sticks. When cooking, kohlrabi works well in stir-fries, soups, and roasted vegetable medleys.
To prepare, peel the outer layer of the bulb. The flesh is most tender near the top. Kohlrabi leaves can be used like kale or collard greens. They make tasty chips when baked or air-fried.
Cultivating Kohlrabi at Home
Growing kohlrabi at home requires proper soil preparation, strategic planting, consistent care, and vigilant pest management. Success lies in understanding the plant’s specific needs and providing optimal conditions throughout its growth cycle.
Soil Preparation and Requirements
Kohlrabi thrives in well-drained, fertile soil with a pH between 6.0 and 7.0. Conduct a soil test to determine the current pH and nutrient levels. Amend the soil with organic matter like compost or well-rotted manure to improve fertility and structure.
Work the soil to a depth of 8-10 inches, removing rocks and debris. If the soil is heavy clay, add sand to improve drainage. Kohlrabi prefers cooler temperatures, so choose a location that receives partial shade in warmer climates.
Incorporate a balanced fertilizer into the soil before planting. A 10-10-10 NPK ratio works well for kohlrabi. Ensure the planting area is free from weeds, which can compete for nutrients and water.
Planting and Spacing
Sow kohlrabi seeds directly in the garden 4-6 weeks before the last spring frost date. For a fall crop, plant 6-8 weeks before the first autumn frost. Plant seeds 1/4 to 1/2 inch deep.
Space seeds 2 inches apart in rows 12-18 inches apart. Once seedlings emerge, thin them to 5-8 inches apart. This spacing allows for proper air circulation and root development.
For transplants, set them out 4-6 weeks before the last spring frost. Space transplants 5-8 inches apart in rows 12-18 inches apart. Water thoroughly after planting to help establish root systems.
Consider using row covers to protect young plants from pests and frost damage. Practice crop rotation to prevent soil depletion and reduce disease risk.
Watering and Fertilizing
Kohlrabi requires consistent moisture for optimal growth. Water deeply once a week, providing 1-1.5 inches of water. Increase frequency during hot, dry periods. Use mulch around plants to retain moisture and suppress weeds.
Apply a side dressing of nitrogen-rich fertilizer when plants are 4-5 inches tall. Use 1/4 cup of balanced fertilizer per 10 feet of row. Avoid over-fertilizing, as this can lead to split bulbs.
For organic gardens, use fish emulsion or compost tea every 2-3 weeks. Ensure fertilizer doesn’t touch plant stems to prevent burning. Water thoroughly after fertilizing to help nutrients reach the root zone.
Managing Pests and Diseases
Common pests affecting kohlrabi include flea beetles, cabbageworms, and aphids. Use floating row covers to prevent insect infestations. For organic control, spray plants with neem oil or insecticidal soap.
Handpick visible pests like cabbageworms. Encourage beneficial insects by planting flowers nearby. Rotate crops annually to disrupt pest life cycles.
Diseases such as clubroot and black rot can affect kohlrabi. Maintain proper spacing and avoid overhead watering to reduce fungal diseases. Remove and destroy infected plants promptly.
Practice good garden hygiene by cleaning tools and removing plant debris. Consider using resistant varieties if certain diseases are prevalent in your area. Monitor plants regularly for signs of stress or disease to catch problems early.
Harvesting and Storage
Proper harvesting and storage techniques are crucial for maintaining the quality and flavor of kohlrabi. Timing, handling, and storage methods all play key roles in preserving this versatile vegetable.
When and How to Harvest Kohlrabi
Kohlrabi is ready for harvest 50 to 70 days after planting, depending on the variety. The ideal time to pick is when the bulbs reach 3 inches in diameter. Larger bulbs may become woody and lose flavor.
To harvest, use a sharp knife to cut the stem at soil level. Alternatively, pull the entire plant from the ground. This method works well in loose soil but may disturb nearby plants.
For a continuous harvest, plant kohlrabi seeds every 2-3 weeks during the growing season. This ensures a steady supply of fresh bulbs.
Post-Harvest Handling
After harvesting, trim the leaves from the stem, leaving about an inch of leaf stems attached. Rinse the bulbs gently to remove dirt.
Sort the kohlrabi, separating any damaged or cracked bulbs for immediate use. Intact bulbs will store longer.
Store freshly harvested kohlrabi in perforated plastic bags in the refrigerator. Maintain high humidity to prevent moisture loss. Under these conditions, kohlrabi can last 2-4 weeks.
Long-Term Storage Solutions
For extended storage, several methods are effective:
Freezing: Blanch peeled, sliced kohlrabi for 3 minutes. Cool rapidly, pack in freezer bags, and store for up to 9 months.
Root cellar storage: Place trimmed bulbs in boxes filled with damp sand. Store in a cool, humid environment (32-40°F, 90-95% humidity). They can last 2-3 months.
Canning: Pressure can peeled, cubed kohlrabi in water or a light brine. This method preserves it for up to a year.
Pickling: Create a tangy treat by pickling kohlrabi slices in vinegar, salt, and spices. Refrigerate and consume within a month.
Canning Kohlrabi
Canning kohlrabi at home preserves this versatile vegetable for future use. The process involves careful preparation, proper canning techniques, and appropriate storage methods to ensure safety and quality.
Preparing Kohlrabi for Canning
Start by thoroughly washing and scrubbing the kohlrabi to remove dirt and debris. Trim off the stems, leaves, and roots. Peel the tough outer skin using a vegetable peeler or knife. Cut the kohlrabi into uniform pieces or shred it using a kitchen slicer or food processor with a medium-sized grating blade.
For pickled kohlrabi, create a brine solution by combining vinegar, water, salt, and desired spices in a pot. Bring this mixture to a boil. Pack the prepared kohlrabi into clean, sterilized canning jars, leaving appropriate headspace.
Canning Process and Techniques
Kohlrabi is best preserved through pickling methods. Fill the jars with hot brine, leaving 1/4 inch of headspace at the top. Remove air bubbles and wipe jar rims clean. Place lids and bands on the jars, tightening to fingertip-tight.
Process the filled jars in a boiling water bath canner. Ensure the water covers the jars by at least an inch. Begin timing once the water returns to a full boil. Process pint jars for approximately 10-20 minutes, adjusting for altitude if necessary.
After processing, remove jars carefully and place them on a towel-lined counter to cool undisturbed.
Storage After Canning
Allow the jars to cool completely at room temperature for 12-24 hours. Check for proper sealing by pressing the center of each lid. A properly sealed lid will not flex.
Remove the bands and lift each jar by the lid to test the seal. Label jars with contents and date. Store sealed jars in a cool, dark place. Properly canned kohlrabi can maintain quality for up to a year.
For best flavor and texture, consume within 3-6 months. Refrigerate any jars that did not seal properly and use within a few weeks. Always inspect canned goods before consumption and discard any showing signs of spoilage.