Frost dates for 18540Scranton, PA
The average last spring frost in Scranton is April 23 and the average first fall frost is October 20, giving a typical growing season of about 178 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 23
- Average first fall frost
- Oct 20
- Growing season
- 178 days
Safer after May 10 (1-in-10 risk)
Possible by Oct 4 (1-in-10 risk)
Last frost typically in 171 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 21 · May 4 · May 22 | Sep 25 · Oct 7 · Oct 22 | 155 days | 100% |
| Frost / freeze (32°F) | Apr 9 · Apr 23 · May 10 | Oct 4 · Oct 20 · Nov 4 | 178 days | 100% |
| Hard freeze (28°F) | Mar 30 · Apr 10 · Apr 26 | Oct 16 · Nov 3 · Nov 19 | 206 days | 100% |
Planting calendar for Scranton
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 23 – May 29 |
| Tomatoes | Transplant outdoors | May 9 – Jun 30 |
| Peppers | Start seeds indoors | Mar 23 – Apr 23 |
| Peppers | Transplant outdoors | May 23 – Jun 23 |
| Eggplant | Start seeds indoors | Apr 9 – May 8 |
| Eggplant | Transplant outdoors | May 23 – Jun 23 |
| Cucumbers | Sow outdoors | May 23 – Jul 10 |
| Summer squash | Sow outdoors | May 9 – Jun 23 |
| Winter squash & pumpkins | Sow outdoors | May 23 – Jun 23 |
| Snap beans | Sow outdoors | May 9 – Aug 2 |
| Sweet corn | Sow outdoors | May 9 – Jun 30 |
| Watermelon & cantaloupe | Sow outdoors | May 23 – Jun 23 |
| Okra | Sow outdoors | May 16 – Jun 8 |
| Peas | Sow outdoors (spring) | Mar 23 – May 8 |
| Potatoes | Plant outdoors (spring) | Mar 23 – May 23 |
| Onions | Start seeds indoors (spring) | Feb 9 – Mar 8 |
| Onions | Transplant outdoors (spring) | Apr 9 – May 8 |
| Broccoli | Start seeds indoors (spring) | Mar 5 – Apr 8 |
| Broccoli | Transplant outdoors (spring) | Apr 9 – May 8 |
| Broccoli | Start seeds indoors (fall) | Jun 20 – Jun 30 |
| Broccoli | Transplant outdoors (fall) | Jul 20 – Jul 31 |
| Cabbage | Start seeds indoors (spring) | Feb 23 – Mar 23 |
| Cabbage | Transplant outdoors (spring) | Mar 23 – Apr 23 |
| Cabbage | Start seeds indoors (fall) | Jun 10 – Jul 10 |
| Cabbage | Transplant outdoors (fall) | Jul 10 – Aug 10 |
| Leaf lettuce | Sow outdoors (spring) | Mar 23 – Jun 8 |
| Leaf lettuce | Sow outdoors (fall) | Jul 10 – Aug 26 |
| Spinach | Sow outdoors (spring) | Mar 16 – Apr 29 |
| Spinach | Sow outdoors (fall) | Jul 27 – Aug 31 |
| Radishes | Sow outdoors (spring) | Mar 23 – May 13 |
| Radishes | Sow outdoors (fall) | Jul 10 – Sep 10 |
| Kale | Sow outdoors (spring) | Apr 9 – Apr 29 |
| Kale | Sow outdoors (fall) | Jul 3 – Aug 10 |
| Carrots | Sow outdoors (spring) | Apr 23 – Jun 8 |
| Carrots | Sow outdoors (fall) | Jun 10 – Jul 26 |
| Garlic | Plant outdoors (fall) | Oct 10 – Nov 10 |
Where these dates come from
ZIP code 18540 is matched to the NOAA station Wilkes-Barre Intl Ap, PA, 10.6 km away, at 930 ft elevation (31 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Wilkes-Barre Intl Ap, PA (used) | 930 ft | Apr 23 | Oct 20 |
| Francis E Walter Dam, PA | 1,509 ft | May 7 | Oct 6 |
| Mt Pocono Mountains Ap, PA | 1,916 ft | May 6 | Oct 8 |
| Hawley 1 E, PA | 890 ft | May 10 | Oct 4 |
Frost dates near Scranton
- Scranton, PA 18501 · last Apr 23, first Oct 20
- Moosic, PA 18507 · last Apr 23, first Oct 20
- Taylor, PA 18517 · last Apr 23, first Oct 20
- Olyphant, PA 18448 · last Apr 23, first Oct 20
- Elmhurst, PA 18416 · last Apr 23, first Oct 20
- Old Forge, PA 18518 · last Apr 23, first Oct 20
- Jessup, PA 18434 · last Apr 23, first Oct 20
- Peckville, PA 18452 · last Apr 23, first Oct 20
Frequently asked questions
- When is the last frost in Scranton, PA?
- For ZIP code 18540, the average last spring frost (32°F) is April 23, based on NOAA 1991-2020 climate normals for the Wilkes-Barre Intl Ap, PA weather station. There is a 1-in-10 chance of a frost after May 10.
- When is the first frost in Scranton, PA?
- The average first fall frost (32°F) is October 20. There is a 1-in-10 chance of frost by October 4, so tender plants are at risk from that point on.
- How long is the growing season in 18540?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 178 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.