Last spring frost
Apr 14
Frost Dates for Poolesville, MD
First fall frost
Oct 29
Growing season
196 days
Hardiness zone
7b
In an average year around Poolesville, MD, the last spring frost (32°F) is about Apr 14 and the first fall frost is about Oct 29, giving roughly a 196-day growing season. To be safe most years, wait until Mar 31 before setting out tender plants.
Last spring frost
Dates the last frost of spring typically ends. Plant tender crops after the risk has passed for your comfort level.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | May 15 | Apr 28 | Apr 14 |
| Freeze (32°F) | May 2 | Apr 14 | Mar 31 |
| Hard (28°F) | Apr 16 | Apr 2 | Mar 18 |
| Severe (24°F) | Apr 5 | Mar 23 | Mar 5 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 15 | May 8 | May 4 | May 1 | Apr 28 | Apr 24 | Apr 22 | Apr 18 | Apr 14 |
| 32°F | May 2 | Apr 25 | Apr 20 | Apr 17 | Apr 14 | Apr 11 | Apr 7 | Apr 3 | Mar 31 |
| 28°F | Apr 16 | Apr 11 | Apr 7 | Apr 4 | Apr 2 | Mar 31 | Mar 28 | Mar 25 | Mar 18 |
| 24°F | Apr 5 | Apr 1 | Mar 29 | Mar 26 | Mar 23 | Mar 19 | Mar 16 | Mar 11 | Mar 5 |
| 20°F | Mar 27 | Mar 22 | Mar 19 | Mar 16 | Mar 12 | Mar 9 | Mar 5 | Feb 28 | Feb 23 |
| 16°F | Mar 20 | Mar 15 | Mar 10 | Mar 6 | Mar 3 | Feb 27 | Feb 22 | Feb 16 | Feb 6 |
First fall frost
Dates the first frost of fall typically arrives. Count back by a crop's days-to-maturity to know your planting cutoff.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Oct 5 | Oct 17 | Oct 31 |
| Freeze (32°F) | Oct 13 | Oct 29 | Nov 12 |
| Hard (28°F) | Oct 26 | Nov 8 | Nov 24 |
| Severe (24°F) | Nov 5 | Nov 20 | Dec 12 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 5 | Oct 9 | Oct 12 | Oct 14 | Oct 17 | Oct 20 | Oct 24 | Oct 27 | Oct 31 |
| 32°F | Oct 13 | Oct 18 | Oct 23 | Oct 26 | Oct 29 | Nov 1 | Nov 3 | Nov 6 | Nov 12 |
| 28°F | Oct 26 | Oct 31 | Nov 2 | Nov 5 | Nov 8 | Nov 11 | Nov 15 | Nov 19 | Nov 24 |
| 24°F | Nov 5 | Nov 9 | Nov 13 | Nov 16 | Nov 20 | Nov 25 | Nov 30 | Dec 4 | Dec 12 |
| 20°F | Nov 15 | Nov 22 | Nov 28 | Dec 2 | Dec 6 | Dec 10 | Dec 16 | Dec 22 | Dec 28 |
| 16°F | Dec 1 | Dec 7 | Dec 14 | Dec 20 | Dec 24 | Dec 28 | Jan 1 | Jan 7 | Jan 16 |
Growing season is measured at 32°F with about 50% probability. Hardiness zone from the 2023 USDA map; frost normals from NOAA 1991-2020.
Where this data comes from
@endif These dates are computed from the nearest official weather station with long-term records: Damascus 3 Ssw, Md, about 12.1 miles away@if(!empty($station['elevation_ft'])), at 700 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.
How we calculate these dates
Frost and freeze dates come from the NOAA 1991–2020 U.S. Climate Normals, the National Oceanic and Atmospheric Administration's 30-year averages for each weather station. A date shown at the 50% level is the median: in half of years the frost falls on or before it. The 10% and 90% columns show the early and late ends of the range, so you can plant on the odds you're comfortable with. These are long-term averages, not a forecast for this year - always check your local outlook before planting.
Source: NOAA National Centers for Environmental Information, 1991–2020 Climate Normals (public domain). Harman is not affiliated with or endorsed by NOAA.
Frequently asked questions
When is the last frost in Poolesville, MD?
On average, the last spring frost (32°F) around Poolesville, MD is about Apr 14. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 31.
When is the first frost in the fall?
The first fall frost around Poolesville, MD typically arrives about Oct 29. Count back by a crop's days to maturity to find the latest date you can plant it.
When can I plant tomatoes and other tender crops?
Tender crops like tomatoes, peppers and basil are damaged by frost, so wait until the last spring frost has passed - around Apr 14 on average, or Mar 31 to be safe most years.
How long is the growing season here?
The frost-free growing season (between the last spring and first fall 32°F frost) is about 196 days in a typical year.
Are these dates a forecast for this year?
No. They are 30-year averages from the NOAA 1991–2020 Climate Normals, not a prediction for the current year. Use them for planning and always check your local weather forecast before planting or protecting crops.
Local weather for 20839 Planting calendar → Maryland frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026