Calendars by city / CT
Hartford, Connecticut vegetable planting calendar
Planting windows for Hartford, Connecticut built from the NOAA 1991–2020 freeze normals at HARTFORD BRADLEY INTERNATIONAL AIRPORT, CT US (station USW00014740), not from a hardiness zone.
Hartford, Connecticut planting dates for 27 vegetables
The same windows as a table
Each row applies a published extension rule to the frost dates above. Hardy crops go out 2–4 weeks before the last frost; semi-hardy crops 0–2 weeks before; tender crops around the frost date; very tender crops 2 or more weeks after. The last fall planting date counts the crop's days to harvest back from the first fall frost. The rules and their sources are on the methodology page.
| Crop | Frost class | Start seeds indoors | Plant outdoors | Last fall planting | Days to harvest |
|---|---|---|---|---|---|
| Beets | Semi-hardy | — (direct sow) | Direct sow: Apr 10 – Apr 24 | Aug 21 | 60 |
| Broccoli | Hardy | Feb 6 – Mar 6 | Transplant: Mar 27 – Apr 10 | Aug 23 | 65 (from transplant) |
| Cabbage | Hardy | Feb 6 – Mar 6 | Transplant: Mar 27 – Apr 10 | Aug 3 | 85 (from transplant) |
| Carrots | Semi-hardy | — (direct sow) | Direct sow: Apr 10 – Apr 24 | Aug 11 | 70 |
| Cauliflower | Semi-hardy | Feb 20 – Mar 20 | Transplant: Apr 10 – Apr 24 | Aug 16 | 65 (from transplant) |
| Kohlrabi | Hardy | — (direct sow) | Direct sow: Mar 27 – Apr 10 | Sep 7 | 50 |
| Lettuce (leaf) | Hardy | — (direct sow) | Direct sow: Mar 27 – Apr 10 | Aug 28 | 60 |
| Onions (green) | Hardy | — (direct sow) | Direct sow: Mar 27 – Apr 10 | Aug 28 | 60 |
| Onions (dry, from seed) | Hardy | — (direct sow) | Direct sow: Mar 27 – Apr 10 | Jul 9 | 110 |
| Onions (dry, from sets) | Hardy | — (direct sow) | Plant sets: Mar 27 – Apr 10 | Jul 9 | 110 |
| Parsnips | Semi-hardy | — (direct sow) | Direct sow: Apr 10 – Apr 24 | Aug 11 | 70 |
| Peas | Hardy | — (direct sow) | Direct sow: Mar 27 – Apr 10 | Aug 23 | 65 |
| Potatoes | Semi-hardy | — (direct sow) | Plant seed potatoes: Apr 10 – Apr 24 | Jun 17 | 125 |
| Radishes | Hardy | — (direct sow) | Direct sow: Mar 27 – Apr 10 | Sep 27 | 30 |
| Spinach | Hardy | — (direct sow) | Direct sow: Mar 27 – Apr 10 | Sep 17 | 40 |
| Swiss chard | Semi-hardy | — (direct sow) | Direct sow: Apr 10 – Apr 24 | Aug 21 | 60 |
| Turnips | Hardy | — (direct sow) | Direct sow: Mar 27 – Apr 10 | Sep 7 | 50 |
| Snap beans | Tender | — (direct sow) | Direct sow: Apr 24 – May 1 | Aug 14 | 60 |
| Cantaloupe | Very tender | Apr 17 – May 8 | Direct sow (or transplant): May 8 – May 22 | Jul 20 | 85 |
| Sweet corn | Tender | — (direct sow) | Direct sow: Apr 24 – May 1 | Jul 15 | 60–90 |
| Cucumbers | Tender | Apr 3 – Apr 17 | Direct sow (or transplant): Apr 24 – May 1 | Aug 19 | 55 |
| Eggplant | Very tender | Mar 6 – Apr 10 | Transplant: May 8 – May 22 | Aug 14 | 60 (from transplant) |
| Peppers | Very tender | Mar 13 – Apr 10 | Transplant: May 8 – May 22 | Aug 4 | 70 (from transplant) |
| Tomatoes | Very tender | Mar 20 – Apr 17 | Transplant: May 8 – May 22 | Aug 9 | 65 (from transplant) |
| Summer squash | Tender | Apr 3 – Apr 17 | Direct sow (or transplant): Apr 24 – May 1 | Aug 24 | 50 |
| Winter squash | Very tender | Apr 17 – May 8 | Direct sow (or transplant): May 8 – May 22 | Jul 5 | 100 |
| Watermelon | Very tender | Apr 17 – May 8 | Direct sow (or transplant): May 8 – May 22 | Jul 20 | 85 |
What the Hartford, Connecticut frost-free season means for your choices
At 172 frost-free days, Hartford, Connecticut gardeners should compare that number to the days-to-harvest column before buying seed. A crop whose days to harvest plus its transplant age is close to the season length needs either an early start indoors or a short-season variety.
- Hardy crops (peas, spinach, radishes, lettuce, broccoli, cabbage) can go in from about Mar 27 – Apr 10 and again for fall.
- Very tender crops (tomatoes, peppers, eggplant, melons, winter squash) should wait until May 8 – May 22; start tomato seeds indoors Mar 20 – Apr 17.
- Fall sowing is worthwhile only for the rows that show a separate fall date; for the others the spring window already covers the season.
Hartford, CT planting questions
When is the last frost in Hartford, Connecticut?
The 50% probability date for the last spring 32°F reading at HARTFORD BRADLEY INTERNATIONAL AIRPORT, CT US is Apr 24, from the NOAA 1991–2020 climate normals. In half the years on that record the last frost came later than that date, so tender crops are safer a week or two after it. The last 28°F hard freeze averages Apr 9.
When can I plant tomatoes in Hartford, Connecticut?
Tomatoes are a very tender crop, so the Colorado State Extension rule puts them out 2 or more weeks after the last spring frost: May 8 – May 22 in Hartford, Connecticut. Start the seeds indoors Mar 20 – Apr 17, which is 5 to 7 weeks before that transplant window.
How long is the growing season in Hartford, Connecticut?
Hartford, Connecticut averages 172 frost-free days, between the 50% last spring frost on Apr 24 and the 50% first fall frost on Oct 13 at HARTFORD BRADLEY INTERNATIONAL AIRPORT, CT US. Check a variety's days to harvest against that number before buying seed.
When should I start seeds indoors in Hartford, Connecticut?
The earliest indoor sowing on this calendar is broccoli and cabbage at Feb 6 – Mar 6. Hardy crops are transplanted out Mar 27 – Apr 10 here, and each crop's indoor window is simply its outdoor window minus the transplant age published by Colorado State Extension, so nothing starts earlier than that.
What can I plant in fall in Hartford, Connecticut?
The crops with a separate fall sowing here, latest first, are radishes, spinach, kohlrabi, turnips, lettuce (leaf) and onions (green), plus 21 more on the chart above. Each fall date counts the crop's days to harvest back from the first fall frost on Oct 13, plus an allowance for frost-tolerant crops that is our own assumption, not the source's.
Station data and limitations
| NOAA station | HARTFORD BRADLEY INTERNATIONAL AIRPORT, CT US (USW00014740) |
|---|---|
| Location | 41.9375, -72.6819 · elevation 53.3 m |
| Last spring 32°F / 28°F (50%) | Apr 24 / Apr 9 |
| First fall 32°F / 28°F (50%) | Oct 13 / Oct 26 |
| Dataset | NOAA/NCEI U.S. Climate Normals 1991–2020, annual/seasonal product, data types ANN-TMIN-PRBLST/PRBFST-T32FP50 and T28FP50 |
| Retrieved | 2026-10-16 |
The normals describe the airport station, not your yard. They are averages of a 30-year record and say nothing about this year's weather. Watch the local forecast around the dates shown, and use soil temperature for warm-season crops, which the Colorado State guide treats as the better signal.
Nearby calendars
- Albany, New York — last spring frost Apr 28
- Boston, Massachusetts — last spring frost Apr 6
- New York City (Central Park), New York — last spring frost Apr 1
- Concord, New Hampshire — last spring frost May 13
Read the method behind these dates: last frost date vs hardiness zone.