Fall in zone 8aPhoto: George Chernilevsky, Public domain, via Wikimedia Commons
Frost dates for ZIP 21866 (Smith Island, 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, St Inigoes Webster Nolf, MD (25 miles away).
Station is a bit far
The nearest station with freeze normals is over 40 km away, so dates here may be off by a week or more.
- Average last spring frostMar 3050% chance of a 32°F freeze after this date
- Average first fall frostNov 1450% chance of a 32°F freeze by this date
- Growing season (frost-free)229 daysmedian, 32°F threshold
- USDA hardiness zone8a10 to 15°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
62°F 55°F or warmer
24-hour average · latest 55°F, as of Oct 18, 2:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Cape Charles 5 ENE (47 mi).
4-inch depth
64°F 55°F or warmer
24-hour average · latest 59°F, as of Oct 18, 2:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Cape Charles 5 ENE (47 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 21866 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
Soil is 64°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 15 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
Prune now
No frost-timed pruning windows are open this week.
Your average first frost is Nov 14: 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 14 |
| 50% (the "average" last frost) | Mar 30 |
| 10% (cautious: only 1 year in 10 freezes later) | Apr 11 |
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 29 |
| 50% (the "average" first frost) | Nov 14 |
| 90% (late: most years have frozen by now) | Dec 1 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | Apr 10 | Nov 1 |
| 32°F (freeze) | Mar 30 | Nov 14 |
| 28°F (hard freeze) | Mar 19 | Nov 29 |
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 21866
Dates count from your average last spring frost (Mar 30) and first fall frost (Nov 14). 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 | Feb 2–16 | Apr 6–20 (transplant) | Jul 18–Aug 15 (transplant) |
| Pepper (sweet and hot) | Jan 19–Feb 2 | Apr 13–27 (transplant) | Jul 25–Aug 15 (transplant) |
| Eggplant | Jan 19–Feb 2 | Apr 13–27 (transplant) | Jul 25–Aug 15 (transplant) |
| Tomatillo | Feb 2–16 | Apr 6–20 (transplant) | – |
| Lettuce | Feb 2–16 | Mar 9–30 (transplant) Mar 2–Apr 13 (sow outdoors) | Sep 19–Oct 10 (transplant) Sep 5–Oct 3 (sowing) |
| Spinach | – | Feb 16–Mar 9 (sow outdoors) | Sep 19–Oct 10 (sowing) |
| Kale | Feb 2–16 | Mar 2–16 (transplant) Mar 2–16 (sow outdoors) | Aug 22–Sep 19 (transplant) Aug 8–Sep 5 (sowing) |
| Collards | Feb 2–16 | Mar 2–30 (transplant) Mar 2–30 (sow outdoors) | Aug 22–Sep 19 (transplant) Aug 8–Sep 5 (sowing) |
| Broccoli | Jan 19–Feb 2 | Mar 2–16 (transplant) | Aug 8–Sep 5 (transplant) |
| Cabbage | Jan 19–Feb 2 | Mar 2–16 (transplant) | Aug 8–Sep 5 (transplant) |
| Cauliflower | Jan 19–Feb 2 | Mar 16–30 (transplant) | Aug 8–Sep 5 (transplant) |
| Brussels sprouts | Jan 5–19 | Mar 2–16 (transplant) | Jul 25–Aug 15 (transplant) |
| Kohlrabi | Feb 2–16 | Mar 2–16 (transplant) Mar 2–16 (sow outdoors) | Sep 5–19 (sowing) |
| Bok choy / Asian greens | – | Mar 2–16 (sow outdoors) | Sep 19–Oct 3 (sowing) |
| Arugula | – | Mar 2–30 (sow outdoors) | Sep 19–Oct 17 (sowing) |
| Mustard greens | – | Mar 2–23 (sow outdoors) | Sep 19–Oct 3 (sowing) |
| Swiss chard | Feb 16–Mar 2 | Mar 16–Apr 6 (transplant) Mar 16–Apr 13 (sow outdoors) | Sep 5–19 (sowing) |
| Beet | – | Mar 2–30 (sow outdoors) | Sep 5–19 (sowing) |
| Carrot | – | Mar 9–Apr 6 (sow outdoors) | Aug 22–Sep 5 (sowing) |
| Radish | – | Feb 23–Apr 6 (sow outdoors) | Oct 3–17 (sowing) |
| Turnip | – | Mar 2–23 (sow outdoors) | Sep 5–19 (sowing) |
| Parsnip | – | Mar 9–30 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Feb 2–Mar 2 (sow outdoors) | Aug 22–Sep 5 (sowing) |
| Onion (bulbing) | Jan 5–19 | Feb 16–Mar 2 (transplant) | – |
| Green onion / scallion | – | Feb 16–Mar 16 (sow outdoors) | Sep 5–19 (sowing) |
| Leek | Jan 5–19 | Mar 2–16 (transplant) | – |
| Garlic | – | – | Oct 3–31 (sowing) |
| Shallot | – | Feb 16–Mar 2 (transplant) | Oct 3–31 (sowing) |
| Potato | – | Mar 2–16 (transplant) | Jul 25–Aug 8 (transplant) |
| Sweet potato | – | Apr 20–May 4 (transplant) | – |
| Sweet corn | – | Apr 6–20 (sow outdoors) | – |
| Bean, bush (snap) | – | Apr 6–20 (sow outdoors) | Aug 22–Sep 5 (sowing) |
| Bean, pole | – | Apr 6–20 (sow outdoors) | – |
| Lima bean | – | Apr 13–27 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | Apr 20–May 11 (sow outdoors) | – |
| Cucumber | Mar 2–9 | Apr 6–20 (transplant) Apr 6–20 (sow outdoors) | Aug 22–Sep 5 (sowing) |
| Summer squash / zucchini | Mar 2–9 | Apr 6–20 (transplant) Apr 6–20 (sow outdoors) | Aug 22–Sep 5 (sowing) |
| Winter squash | Mar 2–9 | Apr 6–20 (transplant) Apr 6–20 (sow outdoors) | – |
| Pumpkin | – | Apr 6–20 (sow outdoors) | – |
| Watermelon | Mar 2–9 | Apr 13–27 (transplant) Apr 13–27 (sow outdoors) | – |
| Cantaloupe / muskmelon | Mar 2–9 | Apr 13–27 (transplant) Apr 13–27 (sow outdoors) | – |
| Okra | Feb 16–Mar 2 | Apr 13–27 (transplant) Apr 13–27 (sow outdoors) | – |
| Celery | Jan 5–19 | Apr 6–13 (transplant) | – |
| Basil | Feb 16–Mar 2 | Apr 6–20 (transplant) Apr 6–20 (sow outdoors) | – |
| Cilantro | – | Mar 16–Apr 13 (sow outdoors) | Sep 19–Oct 3 (sowing) |
| Parsley | Jan 19–Feb 2 | Mar 16–30 (transplant) Mar 9–30 (sow outdoors) | – |
| Dill | – | Mar 30–Apr 13 (sow outdoors) | Sep 19–Oct 3 (sowing) |
| Sunflower | – | Mar 30–Apr 13 (sow outdoors) | – |
| Asparagus (crowns) | – | Mar 2–16 (transplant) | – |
| Rhubarb (crowns) | – | Mar 2–16 (transplant) | – |
| Strawberry (plants) | – | Mar 2–16 (transplant) | Sep 5–Oct 3 (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: St Inigoes Webster Nolf, MD (NOAA GHCN-Daily ID USW00003757), elevation 21 ft, 25.2 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Painter 2 W, VA | 29 mi | Apr 4 | Nov 7 |
| Wallops Island Flight Fac, VA | 30 mi | Mar 31 | Nov 11 |
| Patuxent River NAS, MD | 32 mi | Mar 29 | Nov 15 |
The average last-frost dates of these stations span 6 days, a rough guide to local variation. See data sources & methods.
Frost questions for 21866
When is the last frost in 21866?
The average (50% chance) last spring freeze of 32°F for ZIP 21866 is March 30. For a more cautious planting date, use April 11, when only 1 year in 10 still sees a later freeze.
When is the first frost in 21866?
The average first fall freeze is November 14. In 1 year in 10 it comes by October 29.
What hardiness zone is 21866?
ZIP 21866 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 21866 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
21824 Smith Island 23440 Tangier 21817 Crisfield 21821 Dames Quarter 21838 21867 Fairmount 22539 23427 Saxis
Other ZIP codes in Somerset County
21817 21821 21824 21838 21853 21867 21871 21890 All Somerset County frost dates · Maryland frost dates
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Weekly yard timing, plus frost and soil-temperature alerts for your ZIP code.
- Freeze alerts
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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.