Frost dates for 16021Branchton, PA
The average last spring frost in Branchton is May 7 and the average first fall frost is October 14, giving a typical growing season of about 158 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 7
- Average first fall frost
- Oct 14
- Growing season
- 158 days
Safer after May 25 (1-in-10 risk)
Possible by Oct 1 (1-in-10 risk)
Last frost typically in 185 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) | May 1 · May 20 · Jun 2 | Sep 17 · Oct 1 · Oct 15 | 135 days | 100% |
| Frost / freeze (32°F) | Apr 22 · May 7 · May 25 | Oct 1 · Oct 14 · Oct 30 | 158 days | 100% |
| Hard freeze (28°F) | Apr 11 · Apr 26 · May 15 | Oct 10 · Oct 27 · Nov 10 | 183 days | 100% |
Planting calendar for Branchton
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 | Apr 6 – Jun 12 |
| Tomatoes | Transplant outdoors | May 23 – Jun 24 |
| Peppers | Start seeds indoors | Apr 6 – May 7 |
| Peppers | Transplant outdoors | Jun 6 – Jul 7 |
| Eggplant | Start seeds indoors | Apr 23 – May 22 |
| Eggplant | Transplant outdoors | Jun 6 – Jul 7 |
| Cucumbers | Sow outdoors | Jun 6 – Jul 4 |
| Summer squash | Sow outdoors | May 23 – Jul 7 |
| Winter squash & pumpkins | Sow outdoors | Jun 6 – Jul 7 |
| Snap beans | Sow outdoors | May 23 – Jul 27 |
| Sweet corn | Sow outdoors | May 23 – Jun 24 |
| Watermelon & cantaloupe | Sow outdoors | Jun 6 – Jul 7 |
| Okra | Sow outdoors | May 30 – Jun 22 |
| Peas | Sow outdoors (spring) | Apr 6 – May 22 |
| Potatoes | Plant outdoors (spring) | Apr 6 – Jun 6 |
| Onions | Start seeds indoors (spring) | Feb 23 – Mar 22 |
| Onions | Transplant outdoors (spring) | Apr 23 – May 22 |
| Broccoli | Start seeds indoors (spring) | Mar 19 – Apr 22 |
| Broccoli | Transplant outdoors (spring) | Apr 23 – May 22 |
| Broccoli | Start seeds indoors (fall) | Jun 14 – Jun 24 |
| Broccoli | Transplant outdoors (fall) | Jul 14 – Jul 25 |
| Cabbage | Start seeds indoors (spring) | Mar 9 – Apr 6 |
| Cabbage | Transplant outdoors (spring) | Apr 6 – May 7 |
| Cabbage | Start seeds indoors (fall) | Jun 4 – Jul 4 |
| Cabbage | Transplant outdoors (fall) | Jul 4 – Aug 4 |
| Leaf lettuce | Sow outdoors (spring) | Apr 6 – Jun 22 |
| Leaf lettuce | Sow outdoors (fall) | Jul 4 – Aug 20 |
| Spinach | Sow outdoors (spring) | Mar 30 – May 13 |
| Spinach | Sow outdoors (fall) | Jul 21 – Aug 25 |
| Radishes | Sow outdoors (spring) | Apr 6 – May 27 |
| Radishes | Sow outdoors (fall) | Jul 4 – Sep 4 |
| Kale | Sow outdoors (spring) | Apr 23 – May 13 |
| Kale | Sow outdoors (fall) | Jun 27 – Aug 4 |
| Carrots | Sow outdoors (spring) | May 7 – Jun 22 |
| Carrots | Sow outdoors (fall) | Jun 4 – Jul 20 |
| Garlic | Plant outdoors (fall) | Oct 4 – Nov 4 |
Where these dates come from
ZIP code 16021 is matched to the NOAA station Slippery Rock 1 Ssw, PA, 6.5 km away, at 1,260 ft elevation (59 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Slippery Rock 1 Ssw, PA (used) | 1,260 ft | May 7 | Oct 14 |
| Butler 2 Sw, PA | 1,000 ft | May 7 | Oct 14 |
| Mercer, PA | 1,220 ft | May 15 | Oct 3 |
| New Castle 1 N, PA | 825 ft | Apr 30 | Oct 23 |
Frost dates near Branchton
- Forestville, PA 16035 · last May 7, first Oct 14
- Slippery Rock, PA 16057 · last May 7, first Oct 14
- Boyers, PA 16020 · last May 7, first Oct 14
- Harrisville, PA 16038 · last May 7, first Oct 14
- West Sunbury, PA 16061 · last May 7, first Oct 14
- Grove City, PA 16127 · last May 7, first Oct 14
- Hilliards, PA 16040 · last May 7, first Oct 14
- North Washington, PA 16048 · last May 7, first Oct 14
Frequently asked questions
- When is the last frost in Branchton, PA?
- For ZIP code 16021, the average last spring frost (32°F) is May 7, based on NOAA 1991-2020 climate normals for the Slippery Rock 1 Ssw, PA weather station. There is a 1-in-10 chance of a frost after May 25.
- When is the first frost in Branchton, PA?
- The average first fall frost (32°F) is October 14. There is a 1-in-10 chance of frost by October 1, so tender plants are at risk from that point on.
- How long is the growing season in 16021?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 158 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.