Columbus, Ohio Frost Dates, Growing Season & Hardiness Zone

When is the last frost in Columbus?

In half of years, the last 32°F night has passed by Apr 20. In 1 year out of 10, one still comes after May 7. The last 36°F night (frost possible on plants) typically comes later, around Apr 30, and the last 28°F hard freeze earlier, around Apr 8.

In Columbus, late frosts can come well after the typical date. The safer 1-in-10 date (May 7) is 17 days after the typical date (Apr 20). Tender plants set out early will need cover on cold nights.

Cool nights hang on after the last freeze: the typical last 36°F night (frost possible on plants in low spots) is around Apr 30, 10 days later than the typical last 32°F night. Frost can form on leaves on clear, calm nights even with the thermometer above freezing.

Is it too early to plant in Columbus?

Before Apr 20 the odds of another 32°F night are better than even; after May 7 they are about 1 in 10 or less.

Today's risk is computed in your browser from the same NOAA probability table, shown as the range between the two nearest NOAA probability levels.

When is the first frost in Columbus?

By Oct 24, half of years have had their first 32°F night. In 1 year out of 10, it comes as early as Oct 13. In a typical year, look for the first 36°F night (frost possible on plants) around Oct 13 and the first 28°F hard freeze around Nov 3.

Fall plantings are timed backward from first frost: Oct 24 typically, or Oct 13 if you want a cushion. See the planting calendar for each crop's date.

How long is Columbus's growing season?

A typical year in Columbus has 185 days between the last spring and first fall 32°F nights. In about 1 year in 10, there are fewer than 164 days.

That's enough time for most warm-season vegetables if they go in on time. Long-season crops do best started from transplants.

Growing degree days measure the heat available for crops to grow. The station averages 3,471 a year (base 50°F).

How does Columbus's season compare?

Nationwide, across the 56 cities with frost dates on this site, the typical frost-free season here outlasts the one in 24 of them and falls short of the one in 31.

Growing degree days (base 50°F)

Annual normal: 3,471 GDD (NOAA flag R, 10 years). Running total by the end of each month (sum of NOAA daily GDD normals, so the year-end total can differ slightly from the annual normal):

What growing zone is Columbus? (USDA 2023)

Columbus is in USDA zone 6a–6b on the 2023 map, which means an average coldest winter night of -10 to 0°F. Most of the city was 6a on the 2012 map, and 48 of 49 city ZIPs found in both tables moved up half a zone.

Zones: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed 2026-10-08. Shown as published in the ZIP tables; this page does not show a zone map. Not the official USDA Plant Hardiness Zone Map (official map: planthardiness.ars.usda.gov).

Does the new zone change Columbus's frost dates?

No. A hardiness zone reflects only the average coldest winter temperature, not the timing of spring or fall frost. Columbus's frost dates come from NOAA's 1991–2020 frost probabilities, and the 2023 zone map didn't change them. Pick perennials that survive winter by zone; time your planting by frost dates.

Why do Columbus frost dates differ between websites?

If you've seen Apr 27 listed as Columbus's last frost date, that's the 30%-risk date: about 3 years in 10 still get a 32°F night after it. We lead with Apr 20, the 50% (median) date.

The 'safer' date, May 7, is the 10%-risk date. A 32°F night after it happens in only about 1 year in 10.

Apr 30 is the 50% date for a 36°F night (frost possible on plants), not a 32°F freeze. Sites that treat 36°F as the danger line show later dates.

Sites also pick different weather stations. Within 25 miles of the city center, the 7 stations that meet our quality rules put the typical (50%) last 32°F frost anywhere from Apr 18 to Apr 26 (table below).

Which weather station is this based on?

Station

Columbus WCMH (NOAA USC00331785, COOP)

Distance

3.5 mi NW of the city center

Elevation

740 ft; city center 803 ft (USGS), difference −63 ft

Record

NOAA completeness flag R, 10 of 30 years (1991–2020)

Confidence

Medium (rule)

Confidence: Medium. The station passes our quality rules, but it's farther away or at a different elevation than ideal (3.5 mi, −63 ft; NOAA flag R, 10 of 30 years).

Caveat: these frost statistics carry NOAA's 'R' (representative) flag. They're based on 10 of the 30 years in 1991–2020, with missing months filled in from surrounding stations. The nearest station with a full 'S' (standard) record is Columbus Port Columbus International Airport, 5.6 mi away, with a typical last frost of Apr 18.

Columbus planting dates at a glance

Balanced dates use the 30%-risk last-frost date as the anchor. The Columbus planting calendar has typical and safe dates, fall planting and a month-by-month list for 26 vegetables.

When to plant tomatoes in Columbus · Fall planting dates for Columbus

Frost dates near Columbus

All Ohio cities

Frequently asked questions

What is the average last frost date in Columbus?

Based on NOAA 1991–2020 normals at Columbus WCMH, Columbus's typical last 32°F night is Apr 20. That's the median (50%) date. For a safer target, go with May 7, after which a freeze comes in only about 1 year in 10.

When is the first frost in Columbus?

Expect the first 32°F night by Oct 24 in a typical year, and as early as Oct 13 in about 1 year out of 10. Cold 36°F nights (frost possible on plants) typically start around Oct 13.

What growing zone is Columbus, Ohio?

Zone 6a–6b, on the current 2023 USDA map. Most of Columbus was 6a on the older 2012 map, and you may still see that in older references.

Is it too early to plant in Columbus?

Before Apr 20, yes, for anything frost-tender. Until then, the odds of another 32°F night are better than even. The risk falls from 50% to 10% between Apr 20 and May 7. Peas, lettuce and other cool-season crops can go in weeks earlier; the planting calendar has dates.

What temperature is a killing frost?

It depends on the crop. Tender plants such as tomatoes are killed by a light frost, which CSU Extension describes as 28–32°F; below 28°F is a heavy frost. We show NOAA odds for 36°F (frost possible on plants), 32°F (freeze, our headline) and 28°F (hard freeze).

Is first frost the same as first freeze?

Not exactly. A freeze is about the air reaching 32°F. Frost is ice on surfaces, which can form on calm, clear nights while the air is still a few degrees above freezing. So in Columbus, the first 36°F night (frost possible on plants) typically comes around Oct 13, ahead of the first 32°F night (Oct 24).

Download & sources

• Add Columbus frost & planting dates to your calendar (.ics, 2027)
• Printable planting calendar (PDF)
• How these numbers are calculated

Data: NOAA NCEI U.S. Climate Normals 1991–2020 (annual/seasonal and daily normals, station USC00331785); USDA Plant Hardiness Zone ZIP tables 2023 and 2012 by the PRISM Group, Oregon State University; Census 2020 ZIP/place relationship file; USGS elevation. Long-term odds, not a forecast. Figures and sentences are generated from these data by fixed rules; see the methodology. Last updated 2026-10-08.