Harpster, OH frost dates
Last spring frostApr 29median date
First fall frostOct 17median date
Growing season171 daysfrost-free
Hardiness zone6aZone 6a
How Harpster compares
- In 8 years out of 10, the last spring frost in Harpster falls between April 13 and May 14, a 31-day window. The first fall frost falls between October 2 and October 31.
- The median last frost is 5 days later than the Ohio median of Apr 24.
- Its 171-day growing season is longer than 19% of the 1,063 Ohio places with a regular frost season (state median 180 days).
- The last frost is typical for zone 6a, where the median is Apr 29.
- The weather station records an average of 130 nights a year at or below 32°F.
- Compared with Columbus, OH, 87 km away, the last frost here is 9 days later than there and the growing season is 16 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 13 |
| 50% (median) | April 29 |
| 10% (safe for tender plants) | May 14 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 2 |
| 50% (median) | October 17 |
| 90% (late) | October 31 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Harpster, OH
Harpster, OH frost dates — last frost Apr 29, first frost Oct 17, zone 6a. whenisthelastfrost.com
Crop
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Start indoors: Feb 4 to Feb 18Transplant outside: Apr 1 to Apr 15
Start indoors: Feb 18 to Mar 4Transplant outside: May 13 to May 27
Start indoors: Feb 18 to Mar 4Transplant outside: May 13 to May 27
Start indoors: Mar 4 to Mar 18Transplant outside: May 6 to May 20
Start indoors: Mar 4 to Mar 18Transplant outside: Apr 8 to Apr 22Sow outdoors: Apr 1 to May 6Plant for fall: Aug 22 to Sep 19
Start indoors: Mar 4 to Mar 18Transplant outside: Apr 1 to Apr 15Sow outdoors: Apr 1 to Apr 15Plant for fall: Aug 8 to Aug 29
Start indoors: Mar 4 to Mar 18Transplant outside: Apr 15 to Apr 29Plant for fall: Jul 11 to Aug 1
Start indoors: Mar 4 to Mar 18Transplant outside: Apr 8 to Apr 22Plant for fall: Jul 11 to Aug 1
Start indoors: Mar 4 to Mar 18Transplant outside: Apr 15 to Apr 29Plant for fall: Jul 11 to Aug 1
Start indoors: Mar 18 to Apr 1Transplant outside: May 20 to Jun 3Sow outdoors: May 20 to Jun 3
Start indoors: Mar 18 to Apr 1Transplant outside: May 6 to May 20
Sow outdoors: Mar 18 to Apr 8Plant for fall: Jul 25 to Aug 15
Sow outdoors: Mar 18 to Apr 8Plant for fall: Aug 22 to Sep 12
Sow outdoors: Mar 25 to May 6Plant for fall: Sep 5 to Sep 26
Start indoors: Apr 1 to Apr 8Transplant outside: May 13 to May 20Sow outdoors: May 6 to May 20Plant for fall: Aug 1 to Aug 15
Start indoors: Apr 1 to Apr 8Sow outdoors: May 6 to May 20Plant for fall: Aug 8 to Aug 22
Start indoors: Apr 1 to Apr 8Sow outdoors: May 6 to May 20
Start indoors: Apr 1 to Apr 8Transplant outside: May 13 to May 27
Sow outdoors: Apr 8 to May 6Plant for fall: Jul 25 to Aug 8
Sow outdoors: Apr 8 to May 6Plant for fall: Aug 8 to Aug 22
Sow outdoors: Apr 8 to Apr 29
Sow outdoors: Apr 15 to May 13Plant for fall: Aug 8 to Aug 22
Sow outdoors: Apr 15 to May 6Plant for fall: Aug 22 to Sep 12
Sow outdoors: May 6 to May 27Plant for fall: Aug 1 to Aug 15
Sow outdoors: May 6 to May 20
Transplant outside: May 13 to Jun 3
Plant for fall: Oct 3 to Nov 7
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Harpster, OH
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 4 – Feb 18 | Apr 1 – Apr 15 | — | — |
| Peppers | Feb 18 – Mar 4 | May 13 – May 27 | — | — |
| Eggplant | Feb 18 – Mar 4 | May 13 – May 27 | — | — |
| Tomatoes | Mar 4 – Mar 18 | May 6 – May 20 | — | — |
| Lettuce | Mar 4 – Mar 18 | Apr 8 – Apr 22 | Apr 1 – May 6 | Aug 22 – Sep 19 |
| Kale | Mar 4 – Mar 18 | Apr 1 – Apr 15 | Apr 1 – Apr 15 | Aug 8 – Aug 29 |
| Broccoli | Mar 4 – Mar 18 | Apr 15 – Apr 29 | — | Jul 11 – Aug 1 |
| Cabbage | Mar 4 – Mar 18 | Apr 8 – Apr 22 | — | Jul 11 – Aug 1 |
| Cauliflower | Mar 4 – Mar 18 | Apr 15 – Apr 29 | — | Jul 11 – Aug 1 |
| Okra | Mar 18 – Apr 1 | May 20 – Jun 3 | May 20 – Jun 3 | — |
| Basil | Mar 18 – Apr 1 | May 6 – May 20 | — | — |
| Peas | — | — | Mar 18 – Apr 8 | Jul 25 – Aug 15 |
| Spinach | — | — | Mar 18 – Apr 8 | Aug 22 – Sep 12 |
| Radishes | — | — | Mar 25 – May 6 | Sep 5 – Sep 26 |
| Cucumbers | Apr 1 – Apr 8 | May 13 – May 20 | May 6 – May 20 | Aug 1 – Aug 15 |
| Zucchini & Summer Squash | Apr 1 – Apr 8 | — | May 6 – May 20 | Aug 8 – Aug 22 |
| Winter Squash & Pumpkins | Apr 1 – Apr 8 | — | May 6 – May 20 | — |
| Melons & Watermelon | Apr 1 – Apr 8 | May 13 – May 27 | — | — |
| Carrots | — | — | Apr 8 – May 6 | Jul 25 – Aug 8 |
| Beets | — | — | Apr 8 – May 6 | Aug 8 – Aug 22 |
| Potatoes | — | — | Apr 8 – Apr 29 | — |
| Swiss Chard | — | — | Apr 15 – May 13 | Aug 8 – Aug 22 |
| Cilantro | — | — | Apr 15 – May 6 | Aug 22 – Sep 12 |
| Green Beans | — | — | May 6 – May 27 | Aug 1 – Aug 15 |
| Sweet Corn | — | — | May 6 – May 20 | — |
| Sweet Potatoes | — | May 13 – Jun 3 | — | — |
| Garlic | — | — | — | Oct 3 – Nov 7 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Upper Sandusky, OH weather station, 10 km away (elevation 853 ft (260 m)).
Frost dates near Harpster
- Morral Apr 25 · Oct 20
- Upper Sandusky Apr 29 · Oct 17
- Nevada Apr 29 · Oct 17
- Oceola Apr 19 · Oct 27
- Kirby Apr 29 · Oct 17
- New Bloomington Apr 25 · Oct 20
- Marion Apr 24 · Oct 20
- La Rue Apr 25 · Oct 20
- Sycamore Apr 29 · Oct 17
- Wharton Apr 29 · Oct 17
Frequently asked questions
When is the last frost in Harpster, OH?
The median last spring frost in Harpster, OH is April 29. There is still about a 10% chance of frost after May 14, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Harpster, OH?
The median first fall frost is October 17, with about a 10% chance of frost before October 2.
How long is the growing season in Harpster, OH?
About 171 days between the median last spring frost and first fall frost.
What planting zone is Harpster, OH?
Harpster, OH is in USDA hardiness zone 6a.