Frost dates for 21160Whiteford, MD
The average last spring frost in Whiteford is April 3 and the average first fall frost is November 6, giving a typical growing season of about 217 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 3
- Average first fall frost
- Nov 6
- Growing season
- 217 days
Safer after Apr 18 (1-in-10 risk)
Possible by Oct 26 (1-in-10 risk)
First frost typically in 3 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 3 · Apr 18 · May 5 | Oct 13 · Oct 28 · Nov 7 | 193 days | 100% |
| Frost / freeze (32°F) | Mar 22 · Apr 3 · Apr 18 | Oct 26 · Nov 6 · Nov 19 | 217 days | 100% |
| Hard freeze (28°F) | Mar 8 · Mar 24 · Apr 6 | Nov 4 · Nov 17 · Dec 1 | 238 days | 100% |
Planting calendar for Whiteford
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 3 – May 9 |
| Tomatoes | Transplant outdoors | Apr 19 – Jul 17 |
| Peppers | Start seeds indoors | Mar 3 – Apr 3 |
| Peppers | Transplant outdoors | May 3 – Jun 3 |
| Eggplant | Start seeds indoors | Mar 20 – Apr 18 |
| Eggplant | Transplant outdoors | May 3 – Jun 3 |
| Cucumbers | Sow outdoors | May 3 – Jul 27 |
| Summer squash | Sow outdoors | Apr 19 – Jun 3 |
| Winter squash & pumpkins | Sow outdoors | May 3 – Jun 3 |
| Snap beans | Sow outdoors | Apr 19 – Aug 19 |
| Sweet corn | Sow outdoors | Apr 19 – Jul 17 |
| Watermelon & cantaloupe | Sow outdoors | May 3 – Jun 3 |
| Okra | Sow outdoors | Apr 26 – May 19 |
| Peas | Sow outdoors (spring) | Mar 3 – Apr 18 |
| Potatoes | Plant outdoors (spring) | Mar 3 – May 3 |
| Onions | Start seeds indoors (spring) | Jan 20 – Feb 16 |
| Onions | Transplant outdoors (spring) | Mar 20 – Apr 18 |
| Broccoli | Start seeds indoors (spring) | Feb 13 – Mar 19 |
| Broccoli | Transplant outdoors (spring) | Mar 20 – Apr 18 |
| Broccoli | Start seeds indoors (fall) | Jul 7 – Jul 17 |
| Broccoli | Transplant outdoors (fall) | Aug 6 – Aug 17 |
| Cabbage | Start seeds indoors (spring) | Feb 3 – Mar 3 |
| Cabbage | Transplant outdoors (spring) | Mar 3 – Apr 3 |
| Cabbage | Start seeds indoors (fall) | Jun 27 – Jul 27 |
| Cabbage | Transplant outdoors (fall) | Jul 27 – Aug 27 |
| Leaf lettuce | Sow outdoors (spring) | Mar 3 – May 19 |
| Leaf lettuce | Sow outdoors (fall) | Jul 27 – Sep 12 |
| Spinach | Sow outdoors (spring) | Feb 24 – Apr 9 |
| Spinach | Sow outdoors (fall) | Aug 13 – Sep 17 |
| Radishes | Sow outdoors (spring) | Mar 3 – Apr 23 |
| Radishes | Sow outdoors (fall) | Jul 27 – Sep 27 |
| Kale | Sow outdoors (spring) | Mar 20 – Apr 9 |
| Kale | Sow outdoors (fall) | Jul 20 – Aug 27 |
| Carrots | Sow outdoors (spring) | Apr 3 – May 19 |
| Carrots | Sow outdoors (fall) | Jun 27 – Aug 12 |
| Garlic | Plant outdoors (fall) | Oct 27 – Nov 27 |
Where these dates come from
ZIP code 21160 is matched to the NOAA station Conowingo Dam, MD, 13.4 km away, at 40 ft elevation (354 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Conowingo Dam, MD (used) | 40 ft | Apr 3 | Nov 6 |
| Safe Harbor Dam, PA | 195 ft | Apr 1 | Nov 10 |
| Octoraro Lake, PA | 260 ft | Apr 26 | Oct 22 |
| Aberdeen Phillips Fld, MD | 57 ft | Apr 10 | Oct 30 |
Frost dates near Whiteford
- Delta, PA 17314 · last Apr 1, first Nov 10
- Street, MD 21154 · last Apr 3, first Nov 6
- Pylesville, MD 21132 · last Apr 1, first Nov 10
- Darlington, MD 21034 · last Apr 3, first Nov 6
- Fawn Grove, PA 17321 · last Apr 1, first Nov 10
- Drumore, PA 17518 · last Apr 26, first Oct 22
- Peach Bottom, PA 17563 · last Apr 26, first Oct 22
- Conowingo, MD 21918 · last Apr 3, first Nov 6
Frequently asked questions
- When is the last frost in Whiteford, MD?
- For ZIP code 21160, the average last spring frost (32°F) is April 3, based on NOAA 1991-2020 climate normals for the Conowingo Dam, MD weather station. There is a 1-in-10 chance of a frost after April 18.
- When is the first frost in Whiteford, MD?
- The average first fall frost (32°F) is November 6. There is a 1-in-10 chance of frost by October 26, so tender plants are at risk from that point on.
- How long is the growing season in 21160?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 217 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.