Fall in zone 7aPhoto: Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons
Frost dates for ZIP 21713 (Boonsboro, MD)
Average last spring and first fall frost dates with 10%, 50% and 90% odds, from NOAA's 1991–2020 climate normals for the nearest weather station, Sharpsburg 5 S, MD (9 miles away).
- Average last spring frostApr 2650% chance of a 32°F freeze after this date
- Average first fall frostOct 1850% chance of a 32°F freeze by this date
- Growing season (frost-free)175 daysmedian, 32°F threshold
- USDA hardiness zone7a0 to 5°F avg. coldest night
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This week in your yard
As of Oct 18, 2026, from your frost dates, zone and soil temperature. Lawn timing · Vegetables · Pruning · Plants
Soil temperature now
2-inch depth
63°F 55°F or warmer
24-hour average · latest 60°F, as of Oct 18, 2:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Powder Mill (56 mi).
4-inch depth
63°F 55°F or warmer
24-hour average · latest 58°F, as of Oct 18, 2:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Powder Mill (56 mi).
Fall: Texas A&M AgriLife times fall pre-emergent (for winter weeds such as annual bluegrass) to soil cooling to about 70°F for several days. The 50–55°F band is the spring trigger. Always read and follow the product label.
7-day forecast and frost risk
The latest National Weather Service 7-day forecast and any Frost Advisory or Freeze Warning for 21713 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
Soil is 63°F at 4 inches (estimated soil temperature, not a station reading). Fall pre-emergent (annual bluegrass, winter weeds): window open as soil cools through the 70s and 60s.
Fertilizer window
Lawn region: Transition zone. Timing only; always follow the product label.
- Bermudagrass (warm-season): Spring: Several weeks after the lawn is fully green (April–May) (about Jun 11 here, using green-up about 3–4 weeks after your average last frost); Summer: Every 4–6 weeks through mid-August (heaviest feeder of the group); Late: Light, low-nitrogen/high-potassium feeding about 4 weeks before first frost, or skip. Avoid: Heavy late-fall nitrogen (linked to spring dead spot).
- Tall fescue (cool-season): Early fall: September (main feeding); Late fall: November, while still green; Late winter: Optional light feeding February–March. Avoid: Feeding after mid-spring and through summer in the transition zone (stress and brown patch).
Plant now
No vegetable planting windows are open this week.
Prune now
No frost-timed pruning windows are open this week.
Your average first frost is Oct 18: skip heavy pruning in the 6–8 weeks before it, because new growth may not harden off in time.
Spring-flowering shrubs are pruned right after their flowers fade, not by date. See the pruning guide.
Last spring frost odds
| Chance of a 32°F freeze after this date | Date |
|---|---|
| 90% (early: most years still freeze after this) | Apr 11 |
| 50% (the "average" last frost) | Apr 26 |
| 10% (cautious: only 1 year in 10 freezes later) | May 15 |
Most gardeners plant frost-tender crops (tomatoes, peppers, basil) after the 50% date, and closer to the 10% date for less risk.
First fall frost odds
| Chance the first 32°F freeze has happened by this date | Date |
|---|---|
| 10% (early: 1 year in 10 freezes this soon) | Oct 5 |
| 50% (the "average" first frost) | Oct 18 |
| 90% (late: most years have frozen by now) | Nov 2 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | May 7 | Oct 9 |
| 32°F (freeze) | Apr 26 | Oct 18 |
| 28°F (hard freeze) | Apr 11 | Oct 30 |
n/a means NOAA did not publish a date at that threshold for this station (usually because it rarely gets that cold).
Vegetable planting calendar for 21713
Dates count from your average last spring frost (Apr 26) and first fall frost (Oct 18). Half of years have a frost after the spring date, so give tender crops (tomatoes, peppers, squash) some slack.
| Crop | Start indoors | Spring planting | Fall planting |
|---|---|---|---|
| Tomato | Mar 1–15 | May 3–17 (transplant) | – |
| Pepper (sweet and hot) | Feb 15–Mar 1 | May 10–24 (transplant) | – |
| Eggplant | Feb 15–Mar 1 | May 10–24 (transplant) | – |
| Tomatillo | Mar 1–15 | May 3–17 (transplant) | – |
| Lettuce | Mar 1–15 | Apr 5–26 (transplant) Mar 29–May 10 (sow outdoors) | Aug 23–Sep 13 (transplant) Aug 9–Sep 6 (sowing) |
| Spinach | – | Mar 15–Apr 5 (sow outdoors) | Aug 23–Sep 13 (sowing) |
| Kale | Mar 1–15 | Mar 29–Apr 12 (transplant) Mar 29–Apr 12 (sow outdoors) | Jul 26–Aug 23 (transplant) Jul 12–Aug 9 (sowing) |
| Collards | Mar 1–15 | Mar 29–Apr 26 (transplant) Mar 29–Apr 26 (sow outdoors) | Jul 26–Aug 23 (transplant) Jul 12–Aug 9 (sowing) |
| Broccoli | Feb 15–Mar 1 | Mar 29–Apr 12 (transplant) | Jul 12–Aug 9 (transplant) |
| Cabbage | Feb 15–Mar 1 | Mar 29–Apr 12 (transplant) | Jul 12–Aug 9 (transplant) |
| Cauliflower | Feb 15–Mar 1 | Apr 12–26 (transplant) | Jul 12–Aug 9 (transplant) |
| Brussels sprouts | Feb 1–15 | Mar 29–Apr 12 (transplant) | Jun 28–Jul 19 (transplant) |
| Kohlrabi | Mar 1–15 | Mar 29–Apr 12 (transplant) Mar 29–Apr 12 (sow outdoors) | Aug 9–23 (sowing) |
| Bok choy / Asian greens | – | Mar 29–Apr 12 (sow outdoors) | Aug 23–Sep 6 (sowing) |
| Arugula | – | Mar 29–Apr 26 (sow outdoors) | Aug 23–Sep 20 (sowing) |
| Mustard greens | – | Mar 29–Apr 19 (sow outdoors) | Aug 23–Sep 6 (sowing) |
| Swiss chard | Mar 15–29 | Apr 12–May 3 (transplant) Apr 12–May 10 (sow outdoors) | Aug 9–23 (sowing) |
| Beet | – | Mar 29–Apr 26 (sow outdoors) | Aug 9–23 (sowing) |
| Carrot | – | Apr 5–May 3 (sow outdoors) | Jul 26–Aug 9 (sowing) |
| Radish | – | Mar 22–May 3 (sow outdoors) | Sep 6–20 (sowing) |
| Turnip | – | Mar 29–Apr 19 (sow outdoors) | Aug 9–23 (sowing) |
| Parsnip | – | Apr 5–26 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Mar 1–29 (sow outdoors) | Jul 26–Aug 9 (sowing) |
| Onion (bulbing) | Feb 1–15 | Mar 15–29 (transplant) | – |
| Green onion / scallion | – | Mar 15–Apr 12 (sow outdoors) | Aug 9–23 (sowing) |
| Leek | Feb 1–15 | Mar 29–Apr 12 (transplant) | – |
| Garlic | – | – | Sep 6–Oct 4 (sowing) |
| Shallot | – | Mar 15–29 (transplant) | Sep 6–Oct 4 (sowing) |
| Potato | – | Mar 29–Apr 12 (transplant) | Jun 28–Jul 12 (transplant) |
| Sweet potato | – | May 17–31 (transplant) | – |
| Sweet corn | – | May 3–17 (sow outdoors) | – |
| Bean, bush (snap) | – | May 3–17 (sow outdoors) | – |
| Bean, pole | – | May 3–17 (sow outdoors) | – |
| Lima bean | – | May 10–24 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | May 17–Jun 7 (sow outdoors) | – |
| Cucumber | Mar 29–Apr 5 | May 3–17 (transplant) May 3–17 (sow outdoors) | – |
| Summer squash / zucchini | Mar 29–Apr 5 | May 3–17 (transplant) May 3–17 (sow outdoors) | – |
| Winter squash | Mar 29–Apr 5 | May 3–17 (transplant) May 3–17 (sow outdoors) | – |
| Pumpkin | – | May 3–17 (sow outdoors) | – |
| Watermelon | Mar 29–Apr 5 | May 10–24 (transplant) May 10–24 (sow outdoors) | – |
| Cantaloupe / muskmelon | Mar 29–Apr 5 | May 10–24 (transplant) May 10–24 (sow outdoors) | – |
| Okra | Mar 15–29 | May 10–24 (transplant) May 10–24 (sow outdoors) | – |
| Celery | Feb 1–15 | May 3–10 (transplant) | – |
| Basil | Mar 15–29 | May 3–17 (transplant) May 3–17 (sow outdoors) | – |
| Cilantro | – | Apr 12–May 10 (sow outdoors) | Aug 23–Sep 6 (sowing) |
| Parsley | Feb 15–Mar 1 | Apr 12–26 (transplant) Apr 5–26 (sow outdoors) | – |
| Dill | – | Apr 26–May 10 (sow outdoors) | Aug 23–Sep 6 (sowing) |
| Sunflower | – | Apr 26–May 10 (sow outdoors) | – |
| Asparagus (crowns) | – | Mar 29–Apr 12 (transplant) | – |
| Rhubarb (crowns) | – | Mar 29–Apr 12 (transplant) | – |
| Strawberry (plants) | – | Mar 29–Apr 12 (transplant) | Aug 9–Sep 6 (transplant) |
Typical ranges from university extension planting calendars, adjusted to your frost dates. Probabilities, not guarantees. Fall windows that would overlap spring planting are left out, as are fall crops of frost-tender plants where the frost-free season is under 210 days.
Where these numbers come from
Station: Sharpsburg 5 S, MD (NOAA GHCN-Daily ID USC00188207), elevation 400 ft, 9.2 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Hagerstown 1 E, MD | 8 mi | Apr 11 | Oct 28 |
| Smithsburg 2NW, MD | 11 mi | Apr 25 | Oct 19 |
| Catoctin Mtn Park, MD | 13 mi | Apr 14 | Oct 30 |
The average last-frost dates of these stations span 15 days, a rough guide to local variation. See data sources & methods.
Frost questions for 21713
When is the last frost in 21713?
The average (50% chance) last spring freeze of 32°F for ZIP 21713 is April 26. For a more cautious planting date, use May 15, when only 1 year in 10 still sees a later freeze.
When is the first frost in 21713?
The average first fall freeze is October 18. In 1 year in 10 it comes by October 5.
What hardiness zone is 21713?
ZIP 21713 is in USDA zone 7a (0 to 5°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 21713 right now?
This page shows the latest 2-inch and 4-inch soil temperature from the nearest public soil station (USDA SCAN, NOAA USCRN or TexMesonet), or a labeled estimate when no station is close, against the 50–55°F spring pre-emergent band.
Nearby ZIP codes
21746 21756 Keedysville 21733 St. James 21781 St. James 21734 Funkstown 21773 Myersville 21782 Mercersville 21779 Gapland
Other ZIP codes in Washington County
21711 21715 21719 21722 21733 21734 21740 21742 21746 21750 21756 21767 21779 21781 21782 21783 21795 All Washington County frost dates · Maryland frost dates
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Free. One weekly email plus alerts when your ZIP has a frost or a soil-temperature change worth acting on. After you submit, Kit (our email provider) sends a confirmation email: check your email and click the link to confirm. You aren't subscribed until you do. We collect only your email address and ZIP, sent to Kit to deliver The Dial. Unsubscribe anytime.