Frost dates for 17551Millersville, PA
The average last spring frost in Millersville is April 19 and the average first fall frost is October 24, giving a typical growing season of about 186 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 19
- Average first fall frost
- Oct 24
- Growing season
- 186 days
Safer after May 7 (1-in-10 risk)
Possible by Oct 9 (1-in-10 risk)
Last frost typically in 167 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 19 · May 2 · May 20 | Oct 2 · Oct 13 · Oct 27 | 165 days | 100% |
| Frost / freeze (32°F) | Apr 5 · Apr 19 · May 7 | Oct 9 · Oct 24 · Nov 6 | 186 days | 100% |
| Hard freeze (28°F) | Mar 22 · Apr 5 · Apr 24 | Oct 20 · Nov 4 · Nov 20 | 212 days | 100% |
Planting calendar for Millersville
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 19 – May 25 |
| Tomatoes | Transplant outdoors | May 5 – Jul 4 |
| Peppers | Start seeds indoors | Mar 19 – Apr 19 |
| Peppers | Transplant outdoors | May 19 – Jun 19 |
| Eggplant | Start seeds indoors | Apr 5 – May 4 |
| Eggplant | Transplant outdoors | May 19 – Jun 19 |
| Cucumbers | Sow outdoors | May 19 – Jul 14 |
| Summer squash | Sow outdoors | May 5 – Jun 19 |
| Winter squash & pumpkins | Sow outdoors | May 19 – Jun 19 |
| Snap beans | Sow outdoors | May 5 – Aug 6 |
| Sweet corn | Sow outdoors | May 5 – Jul 4 |
| Watermelon & cantaloupe | Sow outdoors | May 19 – Jun 19 |
| Okra | Sow outdoors | May 12 – Jun 4 |
| Peas | Sow outdoors (spring) | Mar 19 – May 4 |
| Potatoes | Plant outdoors (spring) | Mar 19 – May 19 |
| Onions | Start seeds indoors (spring) | Feb 5 – Mar 4 |
| Onions | Transplant outdoors (spring) | Apr 5 – May 4 |
| Broccoli | Start seeds indoors (spring) | Mar 1 – Apr 4 |
| Broccoli | Transplant outdoors (spring) | Apr 5 – May 4 |
| Broccoli | Start seeds indoors (fall) | Jun 24 – Jul 4 |
| Broccoli | Transplant outdoors (fall) | Jul 24 – Aug 4 |
| Cabbage | Start seeds indoors (spring) | Feb 19 – Mar 19 |
| Cabbage | Transplant outdoors (spring) | Mar 19 – Apr 19 |
| Cabbage | Start seeds indoors (fall) | Jun 14 – Jul 14 |
| Cabbage | Transplant outdoors (fall) | Jul 14 – Aug 14 |
| Leaf lettuce | Sow outdoors (spring) | Mar 19 – Jun 4 |
| Leaf lettuce | Sow outdoors (fall) | Jul 14 – Aug 30 |
| Spinach | Sow outdoors (spring) | Mar 12 – Apr 25 |
| Spinach | Sow outdoors (fall) | Jul 31 – Sep 4 |
| Radishes | Sow outdoors (spring) | Mar 19 – May 9 |
| Radishes | Sow outdoors (fall) | Jul 14 – Sep 14 |
| Kale | Sow outdoors (spring) | Apr 5 – Apr 25 |
| Kale | Sow outdoors (fall) | Jul 7 – Aug 14 |
| Carrots | Sow outdoors (spring) | Apr 19 – Jun 4 |
| Carrots | Sow outdoors (fall) | Jun 14 – Jul 30 |
| Garlic | Plant outdoors (fall) | Oct 14 – Nov 14 |
Where these dates come from
ZIP code 17551 is matched to the NOAA station Lancaster 2Ne Fltr Plt, PA, 9.1 km away, at 270 ft elevation (42 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Lancaster 2Ne Fltr Plt, PA (used) | 270 ft | Apr 19 | Oct 24 |
| Safe Harbor Dam, PA | 195 ft | Apr 1 | Nov 10 |
| Lancaster Ap, PA | 403 ft | Apr 18 | Oct 25 |
| Landisville 2 Nw, PA | 360 ft | Apr 30 | Oct 10 |
Frost dates near Millersville
- Lancaster, PA 17603 · last Apr 19, first Oct 24
- Bausman, PA 17504 · last Apr 18, first Oct 25
- Bart, PA 17503 · last Apr 19, first Oct 24
- Penryn, PA 17564 · last Apr 19, first Oct 24
- Conestoga, PA 17516 · last Apr 1, first Nov 10
- West Willow, PA 17583 · last Apr 19, first Oct 24
- Washington Boro, PA 17582 · last Apr 1, first Nov 10
- Willow Street, PA 17584 · last Apr 19, first Oct 24
Frequently asked questions
- When is the last frost in Millersville, PA?
- For ZIP code 17551, the average last spring frost (32°F) is April 19, based on NOAA 1991-2020 climate normals for the Lancaster 2Ne Fltr Plt, PA weather station. There is a 1-in-10 chance of a frost after May 7.
- When is the first frost in Millersville, PA?
- The average first fall frost (32°F) is October 24. There is a 1-in-10 chance of frost by October 9, so tender plants are at risk from that point on.
- How long is the growing season in 17551?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 186 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.