Columbus, Ohio: planting zone & frost dates
Columbus is in USDA plant hardiness zone 6b, where the average coldest winter night reaches -5 to 0°F (-20.6 to -17.8°C). The typical last spring frost is around Apr 27 and the first fall frost around Oct 20.
Frost dates
| Probability | Last spring frost (32°F) | First fall frost (32°F) |
|---|---|---|
| Safer (10% risk) | May 7 | Oct 13 |
| Typical planning date (30% risk) | Apr 27 | Oct 20 |
| Median (50%) | Apr 20 | Oct 24 |
How to read this: after the spring "10% risk" date, a 32°F frost happens in only about 1 year in 10. In fall, the "10% risk" date is the early end — a frost before it happens about 1 year in 10.
Frost data comes from NOAA station COLUMBUS WCMH, OH (USC00331785), 3.6 mi (5.8 km) from the city center and 66 ft lower than the city center (-20 m). Record used for the 1991–2020 normals: 10 years.
Why your yard may differ from the station: microclimates.
Hardiness zone across Columbus
Columbus spans more than one half-zone. Share of the city's land area by zone (via its 41 ZIP codes): 6b (99%), 6a (1%). The headline zone is the one covering the most land. Look up your ZIP for your exact zone.
ZIP codes in Columbus and their zones
| ZIP | Zone | Share of city land |
|---|---|---|
| 43207 | 6b | 7.8% |
| 43228 | 6b | 6.9% |
| 43219 | 6b | 6.7% |
| 43235 | 6b | 5.1% |
| 43232 | 6b | 4.4% |
| 43137 | 6b | 3.9% |
| 43229 | 6b | 3.9% |
| 43110 | 6b | 3.6% |
| 43204 | 6b | 3.6% |
| 43224 | 6b | 3.1% |
| 43214 | 6b | 3.0% |
| 43223 | 6b | 2.9% |
| 43081 | 6b | 2.8% |
| 43230 | 6b | 2.8% |
| 43123 | 6b | 2.7% |
| 43213 | 6b | 2.4% |
| 43215 | 6b | 2.3% |
| 43026 | 6b | 2.2% |
| 43211 | 6b | 2.0% |
| 43119 | 6b | 1.9% |
| 43227 | 6b | 1.8% |
| 43016 | 6b | 1.7% |
| 43209 | 6b | 1.7% |
| 43201 | 6b | 1.4% |
| 43206 | 6b | 1.4% |
| 43221 | 6b | 1.4% |
| 43231 | 6b | 1.4% |
| 43054 | 6a | 1.3% |
| 43068 | 6b | 1.1% |
| 43125 | 6b | 1.1% |
| 43202 | 6b | 1.1% |
| 43205 | 6b | 1.1% |
| 43220 | 6b | 1.1% |
| 43240 | 6b | 1.1% |
| 43004 | 6b | 1.0% |
| 43203 | 6b | 0.7% |
| 43210 | 6b | 0.7% |
| 43222 | 6b | 0.6% |
| 43002 | 6b | 0.2% |
| 43109 | 6b | 0.1% |
| 43218 | 6b | 0.0% |
Vegetable planting calendar for Columbus
Dates are counted from the 30%-risk frost dates above (last frost Apr 27, first frost Oct 20). Shift a week later in cold spots or low-lying ground.
| Crop | Start indoors | Transplant / plant out | Direct sow | Fall crop sow/plant |
|---|---|---|---|---|
| Tomato | Mar 2 – Mar 16 | May 4 – May 18 | — | — |
| Pepper | Feb 16 – Mar 2 | May 11 – May 25 | — | — |
| Lettuce | Mar 16 – Mar 30 | Apr 13 – May 4 | Mar 30 – May 11 | Aug 11 – Sep 8 |
| Green Beans | — | — | May 4 – Jun 8 | Jul 28 – Aug 11 |
| Sweet Corn | — | — | May 4 – Jun 1 | — |
| Zucchini & Summer Squash | Mar 30 – Apr 6 | May 4 – May 18 | May 4 – May 25 | Jul 28 – Aug 11 |
| Cucumber | Mar 30 – Apr 6 | May 11 – May 18 | May 4 – May 25 | Jul 28 – Aug 11 |
| Carrot | — | — | Apr 6 – May 11 | Jul 28 – Aug 11 |
| Onion | Feb 2 – Feb 16 | Mar 30 – Apr 13 | — | — |
| Potato | — | Mar 30 – Apr 20 | — | — |
| Basil | Mar 16 – Mar 30 | May 11 – May 25 | May 11 – Jun 1 | — |
| Spinach | — | — | Mar 16 – Apr 13 | Aug 25 – Sep 22 |
| Kale | Mar 2 – Mar 16 | Mar 30 – Apr 20 | Mar 30 – Apr 20 | Aug 11 – Sep 8 |
| Broccoli | Mar 2 – Mar 16 | Apr 13 – May 4 | — | Jul 28 – Aug 11 |
| Peas | — | — | Mar 16 – Apr 6 | Aug 11 – Aug 25 |
| Eggplant | Feb 16 – Mar 2 | May 11 – May 25 | — | — |
| Cabbage | Mar 2 – Mar 16 | Mar 30 – Apr 13 | — | Jul 28 – Aug 11 |
| Radish | — | — | Mar 23 – May 11 | Sep 8 – Oct 6 |
| Strawberry | — | Mar 30 – Apr 20 | — | — |
| Beets | — | — | Apr 6 – May 18 | Aug 11 – Aug 25 |
Nearby cities in Ohio
- Dayton — zone 6b, last frost Apr 25, first frost Oct 21
- Cincinnati — zone 6b, last frost Apr 24, first frost Oct 21
- Toledo — zone 6b, last frost Apr 27, first frost Oct 22
- Akron — zone 6b, last frost Apr 30, first frost Oct 22
- Parma — zone 6b, last frost Apr 27, first frost Oct 30
- Cleveland — zone 7a, last frost Apr 14, first frost Nov 7
More: all Ohio cities · other zone 6b cities: Indianapolis, IN, Boston, MA, Detroit, MI, Kansas City, MO, Cincinnati, OH, Pittsburgh, PA, Buffalo, NY, Toledo, OH
Columbus gardening questions
When is the last frost in Columbus, OH?
Plan around Apr 27. At NOAA's Columbus WCMH, OH station, 3.6 mi from the city center, there is a 30% chance of a 32°F frost after that date. Half of springs have their last frost by Apr 20, and after May 7 the risk drops to about 1 in 10. A hard freeze (28°F) usually ends earlier, around Apr 8. The 90% and 10% dates are 32 days apart, close to the 36-day median for cities on this site.
When should I plant tomatoes in Columbus, OH?
Start seeds indoors Mar 2 – Mar 16 and set transplants outside May 4 – May 18, once nights stay above 50°F and the soil is near 60°F. That leaves 176 days between the 30% frost dates, enough for most varieties including 80–85-day slicers. More: tomato planting dates by zone.
How long is the growing season in Columbus?
About 185 days without a 32°F frost in a typical (median) year. In 9 years out of 10 the season lasts at least 164 days, and in 1 year in 10 it runs 203 days or more. In fall there is a 10% chance of frost by Oct 13 and a 30% chance by Oct 20. That is the shortest of the 7 Ohio cities on this site.
When should I plant a fall garden in Columbus?
Count back from the first fall frost (Oct 20): transplant broccoli Jul 28 – Aug 11; sow kale Aug 11 – Sep 8; sow lettuce Aug 11 – Sep 8; sow radishes Sep 8 – Oct 6. Hardy crops keep growing through light frosts; the median 28°F hard freeze here is Nov 3. How the math works: succession and fall planting.
Did Columbus's hardiness zone change on the 2023 map?
Yes. Most of Columbus was zone 6a on the 2012 map and is zone 6b on the 2023 map — half a zone warmer, like about 56% of U.S. ZIP codes. The shift comes from a newer 1991–2020 averaging period plus more weather stations and better mapping; it does not mean last frost comes earlier. Why the 2023 map is warmer.
Is all of Columbus in zone 6b?
No. Zone 6b covers about 99% of the city's land; the rest is in 6a (1%), measured across the city's 41 ZIP codes. Check your own ZIP code in the table above or with the ZIP lookup.