Last spring frost
Apr 14
Frost Dates for Reading, PA
First fall frost
Oct 29
Growing season
197 days
Hardiness zone
7a
In an average year around Reading, PA, the last spring frost (32°F) is about Apr 14 and the first fall frost is about Oct 29, giving roughly a 197-day growing season. To be safe most years, wait until Apr 1 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 13 | Apr 28 | Apr 14 |
| Freeze (32°F) | Apr 30 | Apr 14 | Apr 1 |
| Hard (28°F) | Apr 15 | Apr 1 | Mar 17 |
| Severe (24°F) | Apr 3 | Mar 21 | Mar 5 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 13 | May 7 | May 3 | Apr 30 | Apr 28 | Apr 24 | Apr 22 | Apr 18 | Apr 14 |
| 32°F | Apr 30 | Apr 24 | Apr 21 | Apr 18 | Apr 14 | Apr 11 | Apr 8 | Apr 5 | Apr 1 |
| 28°F | Apr 15 | Apr 10 | Apr 6 | Apr 3 | Apr 1 | Mar 30 | Mar 27 | Mar 22 | Mar 17 |
| 24°F | Apr 3 | Mar 31 | Mar 28 | Mar 24 | Mar 21 | Mar 18 | Mar 14 | Mar 10 | Mar 5 |
| 20°F | Mar 24 | Mar 19 | Mar 16 | Mar 13 | Mar 10 | Mar 6 | Mar 3 | Feb 28 | Feb 22 |
| 16°F | Mar 15 | Mar 9 | Mar 6 | Mar 3 | Feb 28 | Feb 25 | Feb 20 | Feb 14 | 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 4 | Oct 17 | Nov 1 |
| Freeze (32°F) | Oct 13 | Oct 29 | Nov 10 |
| Hard (28°F) | Oct 25 | Nov 8 | Nov 24 |
| Severe (24°F) | Nov 5 | Nov 21 | Dec 8 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 4 | Oct 8 | Oct 11 | Oct 14 | Oct 17 | Oct 20 | Oct 23 | Oct 27 | Nov 1 |
| 32°F | Oct 13 | Oct 19 | Oct 22 | Oct 26 | Oct 29 | Nov 1 | Nov 2 | Nov 6 | Nov 10 |
| 28°F | Oct 25 | Oct 31 | Nov 2 | Nov 5 | Nov 8 | Nov 12 | Nov 15 | Nov 19 | Nov 24 |
| 24°F | Nov 5 | Nov 11 | Nov 14 | Nov 18 | Nov 21 | Nov 25 | Nov 29 | Dec 3 | Dec 8 |
| 20°F | Nov 16 | Nov 24 | Nov 29 | Dec 2 | Dec 5 | Dec 10 | Dec 14 | Dec 20 | Dec 26 |
| 16°F | Dec 1 | Dec 7 | Dec 12 | Dec 18 | Dec 21 | Dec 25 | Dec 31 | Jan 5 | Jan 13 |
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: Reading Spaatz Fld, Pa, about 3.8 miles away@if(!empty($station['elevation_ft'])), at 341 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 Reading, PA?
On average, the last spring frost (32°F) around Reading, PA is about Apr 14. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 1.
When is the first frost in the fall?
The first fall frost around Reading, PA 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 Apr 1 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 197 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 19602 Planting calendar → Pennsylvania frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026