When to plant kohlrabi
Vegetable, hardy
Direct-sow 2–4 weeks before the last frost, or 10–12 weeks before the first killing frost for fall. Standard crops are about 50–60 days; a few varieties in the Wisconsin cultivar list run from 38 to 80 days. Bulbs get woody if they sit too long in heat.
The general rule
- Sow outdoors
- 2–4 weeks before the last spring frost
- Sow for fall
- 10–12 weeks before the first fall frost
- Plant when soil reaches
- 40°F
- Days to maturity
- 50–60 days
What that means in different climates
The same rule applied to the safer frost dates of cities from cold to frost-free.
| City | Last frost · safer | Sow outdoors | Sow for fall |
|---|---|---|---|
| San Jose, CA | Jan 23 | Dec 26 – Jan 9 | Sep 11 – Sep 25 |
| Tucson, AZ | Mar 2 | Feb 2 – Feb 16 | Aug 29 – Sep 12 |
| Portland, OR | Mar 21 | Feb 21 – Mar 7 | Aug 18 – Sep 1 |
| Baltimore, MD | Apr 4 | Mar 7 – Mar 21 | Aug 15 – Aug 29 |
| New York, NY | Apr 12 | Mar 15 – Mar 29 | Aug 14 – Aug 28 |
| Nashville, TN | Apr 16 | Mar 19 – Apr 2 | Jul 26 – Aug 9 |
| Louisville, KY | Apr 23 | Mar 26 – Apr 9 | Jul 29 – Aug 12 |
| Omaha, NE | May 6 | Apr 8 – Apr 22 | Jul 10 – Jul 24 |
| Colorado Springs, CO | May 15 | Apr 17 – May 1 | Jul 4 – Jul 18 |
| Miami, FL | Frost rare | Frost is rare: fall and winter (soil 40°F+). | |