Fall in zone 7bPhoto: Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons
Frost dates for ZIP 19428 (Conshohocken, PA)
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, Norristown, PA (3 miles away).
- Average last spring frostApr 850% chance of a 32°F freeze after this date
- Average first fall frostOct 3150% chance of a 32°F freeze by this date
- Growing season (frost-free)203 daysmedian, 32°F threshold
- USDA hardiness zone7b5 to 10°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
61°F 55°F or warmer
24-hour average · latest 58°F, as of Oct 18, 1:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Avondale 2 N (30 mi).
4-inch depth
62°F 55°F or warmer
24-hour average · latest 60°F, as of Oct 18, 1:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Avondale 2 N (30 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 19428 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
Soil is 62°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 24 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 31: 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 28 |
| 50% (the "average" last frost) | Apr 8 |
| 10% (cautious: only 1 year in 10 freezes later) | Apr 23 |
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 14 |
| 50% (the "average" first frost) | Oct 31 |
| 90% (late: most years have frozen by now) | Nov 12 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | Apr 22 | Oct 20 |
| 32°F (freeze) | Apr 8 | Oct 31 |
| 28°F (hard freeze) | Mar 31 | Nov 10 |
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 19428
Dates count from your average last spring frost (Apr 8) and first fall frost (Oct 31). 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 11–25 | Apr 15–29 (transplant) | – |
| Pepper (sweet and hot) | Jan 28–Feb 11 | Apr 22–May 6 (transplant) | – |
| Eggplant | Jan 28–Feb 11 | Apr 22–May 6 (transplant) | – |
| Tomatillo | Feb 11–25 | Apr 15–29 (transplant) | – |
| Lettuce | Feb 11–25 | Mar 18–Apr 8 (transplant) Mar 11–Apr 22 (sow outdoors) | Sep 5–26 (transplant) Aug 22–Sep 19 (sowing) |
| Spinach | – | Feb 25–Mar 18 (sow outdoors) | Sep 5–26 (sowing) |
| Kale | Feb 11–25 | Mar 11–25 (transplant) Mar 11–25 (sow outdoors) | Aug 8–Sep 5 (transplant) Jul 25–Aug 22 (sowing) |
| Collards | Feb 11–25 | Mar 11–Apr 8 (transplant) Mar 11–Apr 8 (sow outdoors) | Aug 8–Sep 5 (transplant) Jul 25–Aug 22 (sowing) |
| Broccoli | Jan 28–Feb 11 | Mar 11–25 (transplant) | Jul 25–Aug 22 (transplant) |
| Cabbage | Jan 28–Feb 11 | Mar 11–25 (transplant) | Jul 25–Aug 22 (transplant) |
| Cauliflower | Jan 28–Feb 11 | Mar 25–Apr 8 (transplant) | Jul 25–Aug 22 (transplant) |
| Brussels sprouts | Jan 14–28 | Mar 11–25 (transplant) | Jul 11–Aug 1 (transplant) |
| Kohlrabi | Feb 11–25 | Mar 11–25 (transplant) Mar 11–25 (sow outdoors) | Aug 22–Sep 5 (sowing) |
| Bok choy / Asian greens | – | Mar 11–25 (sow outdoors) | Sep 5–19 (sowing) |
| Arugula | – | Mar 11–Apr 8 (sow outdoors) | Sep 5–Oct 3 (sowing) |
| Mustard greens | – | Mar 11–Apr 1 (sow outdoors) | Sep 5–19 (sowing) |
| Swiss chard | Feb 25–Mar 11 | Mar 25–Apr 15 (transplant) Mar 25–Apr 22 (sow outdoors) | Aug 22–Sep 5 (sowing) |
| Beet | – | Mar 11–Apr 8 (sow outdoors) | Aug 22–Sep 5 (sowing) |
| Carrot | – | Mar 18–Apr 15 (sow outdoors) | Aug 8–22 (sowing) |
| Radish | – | Mar 4–Apr 15 (sow outdoors) | Sep 19–Oct 3 (sowing) |
| Turnip | – | Mar 11–Apr 1 (sow outdoors) | Aug 22–Sep 5 (sowing) |
| Parsnip | – | Mar 18–Apr 8 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Feb 11–Mar 11 (sow outdoors) | Aug 8–22 (sowing) |
| Onion (bulbing) | Jan 14–28 | Feb 25–Mar 11 (transplant) | – |
| Green onion / scallion | – | Feb 25–Mar 25 (sow outdoors) | Aug 22–Sep 5 (sowing) |
| Leek | Jan 14–28 | Mar 11–25 (transplant) | – |
| Garlic | – | – | Sep 19–Oct 17 (sowing) |
| Shallot | – | Feb 25–Mar 11 (transplant) | Sep 19–Oct 17 (sowing) |
| Potato | – | Mar 11–25 (transplant) | Jul 11–25 (transplant) |
| Sweet potato | – | Apr 29–May 13 (transplant) | – |
| Sweet corn | – | Apr 15–29 (sow outdoors) | – |
| Bean, bush (snap) | – | Apr 15–29 (sow outdoors) | – |
| Bean, pole | – | Apr 15–29 (sow outdoors) | – |
| Lima bean | – | Apr 22–May 6 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | Apr 29–May 20 (sow outdoors) | – |
| Cucumber | Mar 11–18 | Apr 15–29 (transplant) Apr 15–29 (sow outdoors) | – |
| Summer squash / zucchini | Mar 11–18 | Apr 15–29 (transplant) Apr 15–29 (sow outdoors) | – |
| Winter squash | Mar 11–18 | Apr 15–29 (transplant) Apr 15–29 (sow outdoors) | – |
| Pumpkin | – | Apr 15–29 (sow outdoors) | – |
| Watermelon | Mar 11–18 | Apr 22–May 6 (transplant) Apr 22–May 6 (sow outdoors) | – |
| Cantaloupe / muskmelon | Mar 11–18 | Apr 22–May 6 (transplant) Apr 22–May 6 (sow outdoors) | – |
| Okra | Feb 25–Mar 11 | Apr 22–May 6 (transplant) Apr 22–May 6 (sow outdoors) | – |
| Celery | Jan 14–28 | Apr 15–22 (transplant) | – |
| Basil | Feb 25–Mar 11 | Apr 15–29 (transplant) Apr 15–29 (sow outdoors) | – |
| Cilantro | – | Mar 25–Apr 22 (sow outdoors) | Sep 5–19 (sowing) |
| Parsley | Jan 28–Feb 11 | Mar 25–Apr 8 (transplant) Mar 18–Apr 8 (sow outdoors) | – |
| Dill | – | Apr 8–22 (sow outdoors) | Sep 5–19 (sowing) |
| Sunflower | – | Apr 8–22 (sow outdoors) | – |
| Asparagus (crowns) | – | Mar 11–25 (transplant) | – |
| Rhubarb (crowns) | – | Mar 11–25 (transplant) | – |
| Strawberry (plants) | – | Mar 11–25 (transplant) | Aug 22–Sep 19 (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: Norristown, PA (NOAA GHCN-Daily ID USC00366370), elevation 62 ft, 2.7 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Phoenixville 1 E, PA | 11 mi | Apr 18 | Oct 27 |
| Phila Franklin Inst, PA | 11 mi | Mar 30 | Nov 17 |
| Willow Grove NAS, PA | 12 mi | Apr 11 | Nov 1 |
The average last-frost dates of these stations span 19 days, a rough guide to local variation. See data sources & methods.
Frost questions for 19428
When is the last frost in 19428?
The average (50% chance) last spring freeze of 32°F for ZIP 19428 is April 8. For a more cautious planting date, use April 23, when only 1 year in 10 still sees a later freeze.
When is the first frost in 19428?
The average first fall freeze is October 31. In 1 year in 10 it comes by October 14.
What hardiness zone is 19428?
ZIP 19428 is in USDA zone 7b (5 to 10°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 19428 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
19405 Bridgeport 19035 19444 19462 Plymouth Meeting 19401 Norristown 19085 Villanova 19010 Bryn Mawr 19128 Philadelphia
Other ZIP codes in Montgomery County
18041 18054 18070 18073 18074 18076 18915 18936 18964 18969 19001 19002 19004 19006 19009 19012 19025 19027 19031 19034 19035 19038 19040 19044 All Montgomery County frost dates · Pennsylvania frost dates
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- 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.