Warwick, Rhode Island: planting zone & frost dates
Warwick is in USDA plant hardiness zone 7a, where the average coldest winter night reaches 0 to 5°F (-17.8 to -15.0°C). The typical last spring frost is around Apr 17 and the first fall frost around Oct 24.
Frost dates
| Probability | Last spring frost (32°F) | First fall frost (32°F) |
|---|---|---|
| Safer (10% risk) | Apr 23 | Oct 16 |
| Typical planning date (30% risk) | Apr 17 | Oct 24 |
| Median (50%) | Apr 11 | Oct 30 |
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 PROVIDENCE T F GREEN AP, RI (USW00014765), 1.4 mi (2.3 km) from the city center and 26 ft higher than the city center (+8 m). Record used for the 1991–2020 normals: 30 years.
Why your yard may differ from the station: microclimates.
Hardiness zone across Warwick
All 4 ZIP codes covering Warwick are in zone 7a.
Vegetable planting calendar for Warwick
Dates are counted from the 30%-risk frost dates above (last frost Apr 17, first frost Oct 24). Shift a week later in cold spots or low-lying ground.
| Crop | Start indoors | Transplant / plant out | Direct sow | Fall crop sow/plant |
|---|---|---|---|---|
| Tomato | Feb 20 – Mar 6 | Apr 24 – May 8 | — | — |
| Pepper | Feb 6 – Feb 20 | May 1 – May 15 | — | — |
| Lettuce | Mar 6 – Mar 20 | Apr 3 – Apr 24 | Mar 20 – May 1 | Aug 15 – Sep 12 |
| Green Beans | — | — | Apr 24 – May 29 | Aug 1 – Aug 15 |
| Sweet Corn | — | — | Apr 24 – May 22 | — |
| Zucchini & Summer Squash | Mar 20 – Mar 27 | Apr 24 – May 8 | Apr 24 – May 15 | Aug 1 – Aug 15 |
| Cucumber | Mar 20 – Mar 27 | May 1 – May 8 | Apr 24 – May 15 | Aug 1 – Aug 15 |
| Carrot | — | — | Mar 27 – May 1 | Aug 1 – Aug 15 |
| Onion | Jan 23 – Feb 6 | Mar 20 – Apr 3 | — | — |
| Potato | — | Mar 20 – Apr 10 | — | — |
| Basil | Mar 6 – Mar 20 | May 1 – May 15 | May 1 – May 22 | — |
| Spinach | — | — | Mar 6 – Apr 3 | Aug 29 – Sep 26 |
| Kale | Feb 20 – Mar 6 | Mar 20 – Apr 10 | Mar 20 – Apr 10 | Aug 15 – Sep 12 |
| Broccoli | Feb 20 – Mar 6 | Apr 3 – Apr 24 | — | Aug 1 – Aug 15 |
| Peas | — | — | Mar 6 – Mar 27 | Aug 15 – Aug 29 |
| Eggplant | Feb 6 – Feb 20 | May 1 – May 15 | — | — |
| Cabbage | Feb 20 – Mar 6 | Mar 20 – Apr 3 | — | Aug 1 – Aug 15 |
| Radish | — | — | Mar 13 – May 1 | Sep 12 – Oct 10 |
| Strawberry | — | Mar 20 – Apr 10 | — | — |
| Beets | — | — | Mar 27 – May 8 | Aug 15 – Aug 29 |
Nearby cities in Rhode Island
- Cranston — zone 6b, last frost Apr 17, first frost Oct 24
- Providence — zone 7a, last frost Apr 17, first frost Oct 24
- Pawtucket — zone 7a, last frost Apr 28, first frost Oct 12
More: all Rhode Island cities · other zone 7a cities: Louisville, KY, Wichita, KS, Cleveland, OH, Lexington, KY, St. Louis, MO, Boise, ID, Amarillo, TX, Providence, RI
Warwick gardening questions
When is the last frost in Warwick, RI?
Plan around Apr 17. At NOAA's Providence T F Green Airport, RI station, 1.4 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 11, and after Apr 23 the risk drops to about 1 in 10. A hard freeze (28°F) usually ends earlier, around Apr 1. The last frost is fairly predictable here: only 22 days separate the 90% and 10% dates (median for cities on this site: 36 days).
When should I plant tomatoes in Warwick, RI?
Start seeds indoors Feb 20 – Mar 6 and set transplants outside Apr 24 – May 8, once nights stay above 50°F and the soil is near 60°F. That leaves 190 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 Warwick?
About 199 days without a 32°F frost in a typical (median) year. In 9 years out of 10 the season lasts at least 183 days, and in 1 year in 10 it runs 216 days or more. In fall there is a 10% chance of frost by Oct 16 and a 30% chance by Oct 24. That ranks 3rd longest of 4 Rhode Island cities on this site.
When should I plant a fall garden in Warwick?
Count back from the first fall frost (Oct 24): transplant broccoli Aug 1 – Aug 15; sow kale Aug 15 – Sep 12; sow lettuce Aug 15 – Sep 12; sow radishes Sep 12 – Oct 10. Hardy crops keep growing through light frosts; the median 28°F hard freeze here is Nov 9. How the math works: succession and fall planting.
Did Warwick's hardiness zone change on the 2023 map?
Yes. Most of Warwick was zone 6b on the 2012 map and is zone 7a 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.
How does Warwick compare with Pawtucket, RI?
Both are in zone 7a. The typical last spring frost in Warwick (Apr 17) comes about 11 days earlier than in Pawtucket, RI (Apr 28), 12 miles away, and the first fall frost is Oct 24 versus Oct 12. The two cities use different NOAA stations.