Fall in zone 8aPhoto: George Chernilevsky, Public domain, via Wikimedia Commons
Frost dates for ZIP 20685 (St. Leonard, 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, Solomons, MD (9 miles away).
- Average last spring frostMar 2250% chance of a 32°F freeze after this date
- Average first fall frostNov 2650% chance of a 32°F freeze by this date
- Growing season (frost-free)248 daysmedian, 32°F threshold
- USDA hardiness zone8a10 to 15°F avg. coldest night
Get The Dial for 20685 (St. Leonard)
Frost and freeze alerts from the NWS forecast for 20685, the spring soil-temperature heads-up for pre-emergent, and a short weekly yard-timing email.
- Freeze alerts
- Soil-temp heads-up
- Weekly yard to-dos
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.
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 (44 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 (44 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 20685 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 May 7 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
- Lettuce: fall transplant Oct 1–22
- Spinach: fall sowing Oct 1–22
- Arugula: fall sowing Oct 1–29
- Radish: fall sowing Oct 15–29
- Garlic: fall sowing Oct 15–Nov 12
- Shallot: fall sowing Oct 15–Nov 12
Prune now
No frost-timed pruning windows are open this week.
Your average first frost is Nov 26: 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) | Mar 6 |
| 50% (the "average" last frost) | Mar 22 |
| 10% (cautious: only 1 year in 10 freezes later) | Apr 5 |
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) | Nov 10 |
| 50% (the "average" first frost) | Nov 26 |
| 90% (late: most years have frozen by now) | Dec 12 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | Apr 3 | Nov 13 |
| 32°F (freeze) | Mar 22 | Nov 26 |
| 28°F (hard freeze) | Mar 10 | Dec 9 |
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 20685
Dates count from your average last spring frost (Mar 22) and first fall frost (Nov 26). 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 | Jan 25–Feb 8 | Mar 29–Apr 12 (transplant) | Jul 30–Aug 27 (transplant) |
| Pepper (sweet and hot) | Jan 11–25 | Apr 5–19 (transplant) | Aug 6–27 (transplant) |
| Eggplant | Jan 11–25 | Apr 5–19 (transplant) | Aug 6–27 (transplant) |
| Tomatillo | Jan 25–Feb 8 | Mar 29–Apr 12 (transplant) | – |
| Lettuce | Jan 25–Feb 8 | Mar 1–22 (transplant) Feb 22–Apr 5 (sow outdoors) | Oct 1–22 (transplant) Sep 17–Oct 15 (sowing) |
| Spinach | – | Feb 8–Mar 1 (sow outdoors) | Oct 1–22 (sowing) |
| Kale | Jan 25–Feb 8 | Feb 22–Mar 8 (transplant) Feb 22–Mar 8 (sow outdoors) | Sep 3–Oct 1 (transplant) Aug 20–Sep 17 (sowing) |
| Collards | Jan 25–Feb 8 | Feb 22–Mar 22 (transplant) Feb 22–Mar 22 (sow outdoors) | Sep 3–Oct 1 (transplant) Aug 20–Sep 17 (sowing) |
| Broccoli | Jan 11–25 | Feb 22–Mar 8 (transplant) | Aug 20–Sep 17 (transplant) |
| Cabbage | Jan 11–25 | Feb 22–Mar 8 (transplant) | Aug 20–Sep 17 (transplant) |
| Cauliflower | Jan 11–25 | Mar 8–22 (transplant) | Aug 20–Sep 17 (transplant) |
| Brussels sprouts | Dec 28–Jan 11 | Feb 22–Mar 8 (transplant) | Aug 6–27 (transplant) |
| Kohlrabi | Jan 25–Feb 8 | Feb 22–Mar 8 (transplant) Feb 22–Mar 8 (sow outdoors) | Sep 17–Oct 1 (sowing) |
| Bok choy / Asian greens | – | Feb 22–Mar 8 (sow outdoors) | Oct 1–15 (sowing) |
| Arugula | – | Feb 22–Mar 22 (sow outdoors) | Oct 1–29 (sowing) |
| Mustard greens | – | Feb 22–Mar 15 (sow outdoors) | Oct 1–15 (sowing) |
| Swiss chard | Feb 8–22 | Mar 8–29 (transplant) Mar 8–Apr 5 (sow outdoors) | Sep 17–Oct 1 (sowing) |
| Beet | – | Feb 22–Mar 22 (sow outdoors) | Sep 17–Oct 1 (sowing) |
| Carrot | – | Mar 1–29 (sow outdoors) | Sep 3–17 (sowing) |
| Radish | – | Feb 15–Mar 29 (sow outdoors) | Oct 15–29 (sowing) |
| Turnip | – | Feb 22–Mar 15 (sow outdoors) | Sep 17–Oct 1 (sowing) |
| Parsnip | – | Mar 1–22 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Jan 25–Feb 22 (sow outdoors) | Sep 3–17 (sowing) |
| Onion (bulbing) | Dec 28–Jan 11 | Feb 8–22 (transplant) | – |
| Green onion / scallion | – | Feb 8–Mar 8 (sow outdoors) | Sep 17–Oct 1 (sowing) |
| Leek | Dec 28–Jan 11 | Feb 22–Mar 8 (transplant) | – |
| Garlic | – | – | Oct 15–Nov 12 (sowing) |
| Shallot | – | Feb 8–22 (transplant) | Oct 15–Nov 12 (sowing) |
| Potato | – | Feb 22–Mar 8 (transplant) | Aug 6–20 (transplant) |
| Sweet potato | – | Apr 12–26 (transplant) | – |
| Sweet corn | – | Mar 29–Apr 12 (sow outdoors) | – |
| Bean, bush (snap) | – | Mar 29–Apr 12 (sow outdoors) | Sep 3–17 (sowing) |
| Bean, pole | – | Mar 29–Apr 12 (sow outdoors) | – |
| Lima bean | – | Apr 5–19 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | Apr 12–May 3 (sow outdoors) | – |
| Cucumber | Feb 22–Mar 1 | Mar 29–Apr 12 (transplant) Mar 29–Apr 12 (sow outdoors) | Sep 3–17 (sowing) |
| Summer squash / zucchini | Feb 22–Mar 1 | Mar 29–Apr 12 (transplant) Mar 29–Apr 12 (sow outdoors) | Sep 3–17 (sowing) |
| Winter squash | Feb 22–Mar 1 | Mar 29–Apr 12 (transplant) Mar 29–Apr 12 (sow outdoors) | – |
| Pumpkin | – | Mar 29–Apr 12 (sow outdoors) | – |
| Watermelon | Feb 22–Mar 1 | Apr 5–19 (transplant) Apr 5–19 (sow outdoors) | – |
| Cantaloupe / muskmelon | Feb 22–Mar 1 | Apr 5–19 (transplant) Apr 5–19 (sow outdoors) | – |
| Okra | Feb 8–22 | Apr 5–19 (transplant) Apr 5–19 (sow outdoors) | – |
| Celery | Dec 28–Jan 11 | Mar 29–Apr 5 (transplant) | – |
| Basil | Feb 8–22 | Mar 29–Apr 12 (transplant) Mar 29–Apr 12 (sow outdoors) | – |
| Cilantro | – | Mar 8–Apr 5 (sow outdoors) | Oct 1–15 (sowing) |
| Parsley | Jan 11–25 | Mar 8–22 (transplant) Mar 1–22 (sow outdoors) | – |
| Dill | – | Mar 22–Apr 5 (sow outdoors) | Oct 1–15 (sowing) |
| Sunflower | – | Mar 22–Apr 5 (sow outdoors) | – |
| Asparagus (crowns) | – | Feb 22–Mar 8 (transplant) | – |
| Rhubarb (crowns) | – | Feb 22–Mar 8 (transplant) | – |
| Strawberry (plants) | – | Feb 22–Mar 8 (transplant) | Sep 17–Oct 15 (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: Solomons, MD (NOAA GHCN-Daily ID USC00188405), elevation 12 ft, 8.9 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Patuxent River NAS, MD | 11 mi | Mar 29 | Nov 15 |
| Mechanicsville 5 NE, MD | 11 mi | Apr 17 | Oct 27 |
| St Inigoes Webster Nolf, MD | 21 mi | Mar 30 | Nov 14 |
The average last-frost dates of these stations span 26 days, a rough guide to local variation. See data sources & methods.
Frost questions for 20685
When is the last frost in 20685?
The average (50% chance) last spring freeze of 32°F for ZIP 20685 is March 22. For a more cautious planting date, use April 5, when only 1 year in 10 still sees a later freeze.
When is the first frost in 20685?
The average first fall freeze is November 26. In 1 year in 10 it comes by November 10.
What hardiness zone is 20685?
ZIP 20685 is in USDA zone 8a (10 to 15°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 20685 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
20615 Broomes Island 20676 20657 Chesapeake Ranch Estates 20636 20678 Prince Frederick 20629 Solomons 20688 Solomons 20612 Benedict
Other ZIP codes in Calvert County
20615 20629 20639 20657 20676 20678 20688 20689 20732 20736 20754 All Calvert County frost dates · Maryland frost dates
Never miss a frost: get The Dial
Weekly yard timing, plus frost and soil-temperature alerts for your ZIP code.
- Freeze alerts
- Soil-temp heads-up
- Weekly yard to-dos
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.