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Showing dates for Purple Kohlrabi Microgreens in USDA Zone 7
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Purple Kohlrabi Microgreens · Zones 2–11
Growing Details
Zone-by-Zone Planting Calendar
| Zone | Indoor Start | Transplant | Direct Sow | Harvest |
|---|---|---|---|---|
| Zone 3 | January – December | — | — | January – December |
| Zone 4 | January – December | — | — | January – December |
| Zone 5 | January – December | — | — | January – December |
| Zone 6 | January – December | — | — | January – December |
| Zone 7 | January – December | — | — | January – December |
| Zone 8 | January – December | — | — | January – December |
| Zone 9 | January – December | — | — | January – December |
| Zone 10 | January – December | — | — | January – December |
Complete Growing Guide
Growing purple kohlrabi microgreens requires minimal space but precise timing to achieve those stunning purple stems. Start by preparing your growing trays with a well-draining seed starting mix or coconut coir, filling to about 1-2 inches deep. The medium should hold moisture without becoming waterlogged, as brassica seeds are prone to damping off in overly wet conditions.
Unlike some microgreen varieties, purple kohlrabi seeds don't require pre-soaking. Scatter seeds evenly across your moistened growing medium at a density of approximately 2-3 tablespoons per 10x20 inch tray. You want good coverage without overcrowding, which can lead to poor air circulation and fungal issues. Lightly press seeds into the medium and mist thoroughly with a fine spray bottle.
Cover your trays with another inverted tray or humidity dome to create darkness during germination. Purple kohlrabi seeds germinate best in temperatures between 65-75°F. Check daily and remove the cover once you see the first cotyledons pushing through the soil, typically within 2-4 days.
Once uncovered, provide 12-16 hours of bright indirect light or LED grow lights positioned 12-18 inches above the trays. Direct sunlight can scorch young microgreens and cause uneven growth. Maintain consistent moisture by bottom-watering or using a gentle misting technique, always watering in the morning to prevent overnight fungal problems.
The key to developing those characteristic purple stems is providing adequate light intensity while maintaining proper growing temperatures. Too little light results in pale, leggy growth, while excessive heat can cause bolting. Monitor your microgreens daily and rotate trays if using directional lighting to ensure even development.
Common mistakes include overwatering, insufficient air circulation, and harvesting too early before the purple coloration fully develops. Watch for the development of the first true leaves as a signal that harvest time is approaching.
Harvesting
Purple kohlrabi microgreens are ready for harvest when they reach 2-3 inches tall with well-developed cotyledon leaves and visible purple stem coloration, typically 8-12 days after sowing. The purple stems should be vibrant and the green cotyledon leaves fully expanded and uniform in size.
Harvest in the morning when the microgreens are most turgid and flavorful. Use clean, sharp scissors or a microgreen harvesting knife to cut just above the soil line, leaving about 1/4 inch of stem. Cut in small sections rather than attempting to harvest entire trays at once, as this maintains freshness.
Test readiness by gently tugging a few microgreens - they should resist pulling and feel substantial rather than thin and wispy. The cotyledons should have a bright green color with no yellowing, and the purple stems should be crisp and snappy when bent. Avoid harvesting if morning dew or excess moisture is present, as this can lead to faster deterioration during storage.
Storage & Preservation
Fresh purple kohlrabi microgreens store best when harvested dry and immediately placed in breathable containers. Use plastic clamshell containers lined with paper towels or perforated bags to maintain proper humidity while allowing air circulation. Store in the refrigerator at 32-35°F with 90-95% humidity for optimal shelf life of 7-10 days.
For longer preservation, purple kohlrabi microgreens can be flash-frozen on parchment-lined trays before transferring to freezer bags, though this changes their texture and makes them suitable only for smoothies or cooked applications. Dehydrating at low temperatures (95-105°F) creates a concentrated garnish that retains the peppery flavor while losing the fresh crunch. Unlike mature kohlrabi, microgreens aren't suitable for traditional preservation methods like fermentation or canning due to their delicate structure.
History & Origin
Purple kohlrabi microgreens represent a modern adaptation of an ancient vegetable with a fascinating European heritage. Kohlrabi itself originated from wild cabbage along the Mediterranean coast and was first documented in Northern Europe around the 15th century. The name derives from German 'kohl' (cabbage) and 'rabi' (turnip), reflecting its unique appearance.
The purple varieties of kohlrabi were developed through selective breeding in the 19th century, particularly in German and Austrian agricultural regions where the vegetable became a staple crop. The deep purple coloration comes from anthocyanins, the same compounds that give red cabbage its color.
The cultivation of kohlrabi as microgreens is a 21st-century innovation, part of the broader microgreens movement that began in California in the 1980s. Purple kohlrabi microgreens became popular among commercial growers and home enthusiasts around 2010 as the visual appeal of colorful microgreens gained traction in restaurants and farmers markets. Today's purple kohlrabi microgreen varieties are typically hybrid selections bred specifically for their vibrant stem color and rapid, uniform germination.
Advantages
- +Striking visual contrast with purple stems and bright green cotyledons perfect for garnishes
- +No seed soaking required, making them faster to start than many microgreen varieties
- +Excellent shelf life of 7-10 days when properly stored, longer than most microgreens
- +Reliable germination rates typically exceeding 85% under proper conditions
- +More complex flavor profile than standard cabbage microgreens with distinctive peppery notes
- +Good resistance to common microgreen diseases like damping off compared to more delicate varieties
- +Fast growing cycle allows for quick succession planting and consistent harvests
Considerations
- -Purple coloration may not fully develop under insufficient light conditions
- -More expensive seeds compared to basic brassica microgreen varieties
- -Can become bitter if allowed to grow past optimal harvest window
- -Requires precise moisture management as overwatering quickly leads to root rot
- -Growth can be uneven if temperature fluctuates outside the 65-75°F range
Companion Plants
Plant Together
Lettuce
Similar growing conditions and harvest timing, efficient space utilization
Radish Microgreens
Compatible brassica family member with similar care requirements
Arugula Microgreens
Fellow brassica with complementary spicy flavor profile
Pea Shoots
Nitrogen-fixing properties benefit soil health for successive plantings
Chives
Natural pest deterrent against aphids and flea beetles
Cilantro
Attracts beneficial insects and provides flavor contrast
Spinach Microgreens
Similar light and moisture requirements, good companion crop
Nasturtium
Acts as trap crop for flea beetles and aphids that target brassicas
Keep Apart
Fennel
Allelopathic compounds inhibit growth of brassica family plants
Strawberries
May stunt growth of brassicas through root competition
Tomatoes
Different pH and nutrient requirements can negatively impact kohlrabi growth
Pests & Disease Resistance
Resistance
Good resistance typical of brassicas
Common Pests
Flea beetles, aphids
Diseases
Clubroot, black rot, damping off