Purple Kohlrabi Growing Guide
Brassicaceae family
Days to Harvest55 days
SunlightFull Sun
Frost ToleranceModerate
Spacing4/sqft (6" apart)
Germination5-10 days
HardinessHardy
Germ. Temp65°F
Start Indoors6 weeks before last frost
Growth Stages
- Seedling
- Vegetative / Root Development
- Mature / Harvest Ready
Planting Dates by Zone
| Zone | Start Indoors | Transplant | Direct Sow | Harvest |
|---|---|---|---|---|
| Zone 1a | Apr 13 | May 4 | May 4 | Jun 13 |
| Zone 1b | Apr 13 | May 4 | May 4 | Jun 13 |
| Zone 2a | Apr 3 | Apr 24 | Apr 24 | Jun 3 |
| Zone 2b | Apr 13 | May 4 | May 4 | Jun 13 |
| Zone 3a | Apr 10 | May 1 | May 1 | Jun 10 |
| Zone 3b | Apr 3 | Apr 24 | Apr 24 | Jun 3 |
| Zone 4a | Mar 24 | Apr 14 | Apr 14 | May 24 |
| Zone 4b | Mar 20 | Apr 10 | Apr 10 | May 20 |
| Zone 5a | Mar 17 | Apr 7 | Apr 7 | May 17 |
| Zone 5b | Mar 17 | Apr 7 | Apr 7 | May 17 |
| Zone 6a | Mar 17 | Apr 7 | Apr 7 | May 17 |
| Zone 6b | Mar 4 | Mar 25 | Mar 25 | May 4 |
| Zone 7a | Mar 4 | Mar 25 | Mar 25 | May 4 |
| Zone 7b | Feb 27 | Mar 20 | Mar 20 | Apr 29 |
| Zone 8a | Feb 22 | Mar 15 | Mar 15 | Apr 24 |
| Zone 8b | Feb 8 | Mar 1 | Mar 1 | Apr 10 |
| Zone 9a | Feb 6 | Feb 27 | Feb 27 | Apr 8 |
| Zone 9b | Jan 27 | Feb 17 | Feb 17 | Mar 29 |
| Zone 10a | Jan 9 | Jan 30 | Jan 30 | Mar 11 |
| Zone 10b | Dec 17 | Jan 7 | Jan 7 | Feb 16 |
| Zone 11a | Dec 17 | Jan 7 | Jan 7 | Feb 16 |
| Zone 11b | Dec 4 | Dec 25 | Dec 25 | Feb 3 |
| Zone 12a | Nov 20 | Dec 11 | Dec 11 | Jan 20 |
| Zone 12b | Nov 20 | Dec 11 | Dec 11 | Jan 20 |
| Zone 13a | Nov 20 | Dec 11 | Dec 11 | Jan 20 |
| Zone 13b | Nov 20 | Dec 11 | Dec 11 | Jan 20 |
Frequently Asked Questions
How long does it take to grow Purple Kohlrabi?
Purple Kohlrabi takes approximately 55 days from planting to harvest.
How much sun does Purple Kohlrabi need?
Purple Kohlrabi requires full sun (6+ hours direct sunlight per day).
How far apart should I plant Purple Kohlrabi?
Plant Purple Kohlrabi at 4/sqft (6" apart) using square foot gardening spacing.
Can Purple Kohlrabi survive frost?
Purple Kohlrabi is tolerant of moderate frost.
How long does Purple Kohlrabi take to germinate?
Purple Kohlrabi seeds germinate in 5-10 days at an optimal temperature of 65°F.
When should I start Purple Kohlrabi seeds indoors?
Start Purple Kohlrabi seeds indoors 6 weeks before your last frost date, then transplant -3 weeks after last frost.
Plan Your Purple Kohlrabi Garden
Track Purple Kohlrabi from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.
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