Frost dates for 01890Winchester, MA
The average last spring frost in Winchester is April 25 and the average first fall frost is October 17, giving a typical growing season of about 174 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 25
- Average first fall frost
- Oct 17
- Growing season
- 174 days
Safer after May 8 (1-in-10 risk)
Possible by Oct 3 (1-in-10 risk)
Last frost typically in 175 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | Apr 26 · May 7 · May 20 | Sep 26 · Oct 6 · Oct 20 | 151 days | 100% |
| Frost / freeze (32°F) | Apr 13 · Apr 25 · May 8 | Oct 3 · Oct 17 · Nov 1 | 174 days | 100% |
| Hard freeze (28°F) | Mar 31 · Apr 11 · Apr 24 | Oct 14 · Oct 30 · Nov 11 | 201 days | 100% |
Planting calendar for Winchester
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Mar 25 – May 31 |
| Tomatoes | Transplant outdoors | May 11 – Jun 27 |
| Peppers | Start seeds indoors | Mar 25 – Apr 25 |
| Peppers | Transplant outdoors | May 25 – Jun 25 |
| Eggplant | Start seeds indoors | Apr 11 – May 10 |
| Eggplant | Transplant outdoors | May 25 – Jun 25 |
| Cucumbers | Sow outdoors | May 25 – Jul 7 |
| Summer squash | Sow outdoors | May 11 – Jun 25 |
| Winter squash & pumpkins | Sow outdoors | May 25 – Jun 25 |
| Snap beans | Sow outdoors | May 11 – Jul 30 |
| Sweet corn | Sow outdoors | May 11 – Jun 27 |
| Watermelon & cantaloupe | Sow outdoors | May 25 – Jun 25 |
| Okra | Sow outdoors | May 18 – Jun 10 |
| Peas | Sow outdoors (spring) | Mar 25 – May 10 |
| Potatoes | Plant outdoors (spring) | Mar 25 – May 25 |
| Onions | Start seeds indoors (spring) | Feb 11 – Mar 10 |
| Onions | Transplant outdoors (spring) | Apr 11 – May 10 |
| Broccoli | Start seeds indoors (spring) | Mar 7 – Apr 10 |
| Broccoli | Transplant outdoors (spring) | Apr 11 – May 10 |
| Broccoli | Start seeds indoors (fall) | Jun 17 – Jun 27 |
| Broccoli | Transplant outdoors (fall) | Jul 17 – Jul 28 |
| Cabbage | Start seeds indoors (spring) | Feb 25 – Mar 25 |
| Cabbage | Transplant outdoors (spring) | Mar 25 – Apr 25 |
| Cabbage | Start seeds indoors (fall) | Jun 7 – Jul 7 |
| Cabbage | Transplant outdoors (fall) | Jul 7 – Aug 7 |
| Leaf lettuce | Sow outdoors (spring) | Mar 25 – Jun 10 |
| Leaf lettuce | Sow outdoors (fall) | Jul 7 – Aug 23 |
| Spinach | Sow outdoors (spring) | Mar 18 – May 1 |
| Spinach | Sow outdoors (fall) | Jul 24 – Aug 28 |
| Radishes | Sow outdoors (spring) | Mar 25 – May 15 |
| Radishes | Sow outdoors (fall) | Jul 7 – Sep 7 |
| Kale | Sow outdoors (spring) | Apr 11 – May 1 |
| Kale | Sow outdoors (fall) | Jun 30 – Aug 7 |
| Carrots | Sow outdoors (spring) | Apr 25 – Jun 10 |
| Carrots | Sow outdoors (fall) | Jun 7 – Jul 23 |
| Garlic | Plant outdoors (fall) | Oct 7 – Nov 7 |
Where these dates come from
ZIP code 01890 is matched to the NOAA station Reading, MA, 8 km away, at 110 ft elevation (54 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Reading, MA (used) | 110 ft | Apr 25 | Oct 17 |
| Bedford, MA | 160 ft | Apr 27 | Oct 13 |
| Bedford Hanscom Fld, MA | 133 ft | Apr 28 | Oct 10 |
| Boston Logan Intl Ap, MA | 12 ft | Apr 4 | Nov 9 |
Frost dates near Winchester
- Woburn, MA 01813 · last Apr 25, first Oct 17
- West Medford, MA 02156 · last Apr 4, first Nov 9
- Arlington, MA 02474 · last Apr 25, first Oct 17
- Arlington Heights, MA 02475 · last Apr 27, first Oct 13
- Medford, MA 02155 · last Apr 4, first Nov 9
- Stoneham, MA 02180 · last Apr 25, first Oct 17
- Lexington, MA 02420 · last Apr 27, first Oct 13
- Somerville, MA 02144 · last Apr 4, first Nov 9
Frequently asked questions
- When is the last frost in Winchester, MA?
- For ZIP code 01890, the average last spring frost (32°F) is April 25, based on NOAA 1991-2020 climate normals for the Reading, MA weather station. There is a 1-in-10 chance of a frost after May 8.
- When is the first frost in Winchester, MA?
- The average first fall frost (32°F) is October 17. There is a 1-in-10 chance of frost by October 3, so tender plants are at risk from that point on.
- How long is the growing season in 01890?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 174 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.