Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated

Planting zone for 19494 — Valley Forge, PA

ZIP code 19494 (Valley Forge, Chester County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 18 and the first fall frost October 27.

Where ZIP 19494 is

tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zone7a0 to 5 °F
Coldest night−17.8 to −15 °C
Last frostApr 18
First frostOct 27
2012 zone6b

Was 6b on the 2012 map — half a zone warmer now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 7a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Valley Forge, PA…

Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates in Valley Forge, PA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 18median — 50% chance of a later frost
Safe for tender plantsMay 4only 10% chance of frost after
First fall frostOctober 27median — 10% chance by Oct 12
Growing season192 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 3 and returns around November 6.

From the NOAA station Phoenixville 1 E, PA — 2 miles away, elevation 85 ft. NOAA NCEI U.S. Climate Normals 1991–2020, 32 °F threshold. Low spots and valleys can freeze later in spring than the station.

When to plant vegetables in 19494

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 7 – Mar 21
SpinachSow outdoors · Mar 7 – Mar 28
Broccoli, cabbageStart indoors · Feb 7 – Feb 21
Broccoli, cabbageTransplant · Mar 28 – Apr 11
Onion setsPlant outdoors · Mar 21 – Apr 4
PotatoesPlant outdoors · Mar 28 – Apr 11
LettuceSow outdoors · Mar 21 – Apr 4
Carrots, beetsSow outdoors · Mar 28 – Apr 11
TomatoesStart indoors · Feb 21 – Mar 7
TomatoesTransplant · Apr 25 – May 9
Peppers, eggplantStart indoors · Feb 7 – Feb 21
Peppers, eggplantTransplant · May 2 – May 16
BeansSow outdoors · Apr 25 – May 9
Sweet cornSow outdoors · Apr 25 – May 9
Cucumbers, squashSow outdoors · Apr 25 – May 9
Fall lettuce, spinachSow outdoors · Sep 1 – Sep 15
GarlicPlant cloves · Oct 13 – Nov 17
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 18) and first fall frost (Oct 27) with the rules of thumb U.S. extension services publish. Cool-season crops take a light frost; warm-season crops do best once the soil is above about 60 °F.

When spring arrived in 2026

In 2026, spring leaf-out near 19494 came on Mar 22 — 3 days earlier than the 1991–2020 average (Mar 25).

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Native plants for zone 7a in Pennsylvania

620 plants native to the lower 48 states, recorded in Pennsylvania, and rated by the USDA to survive 0 °F or colder — the bottom of zone 7a. Each links to its USDA PLANTS profile.

Trees 78

American basswood100 ft · blooms late spring · low shade tolerance · to −46 °FAmerican beech80 ft · blooms mid spring · low shade tolerance · to −44 °FAmerican chestnut115 ft · blooms early summer · high shade tolerance · to −33 °FAmerican elm120 ft · blooms early spring · medium shade tolerance · to −46 °FAmerican sycamore100 ft · blooms spring · medium shade tolerance · to −34 °Farborvitae50 ft · blooms mid spring · medium shade tolerance · to −33 °F

Shrubs 123

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °FAllegheny serviceberry35 ft · blooms early spring · low shade tolerance · to −38 °Falternateleaf dogwood25 ft · blooms mid spring · low shade tolerance · to −47 °FAmerican black currant3 ft · blooms early spring · to −46 °FAmerican hazelnut10 ft · blooms spring · medium shade tolerance · to −33 °FAmerican holly40 ft · blooms mid spring · low shade tolerance · to −20 °F

Wildflowers & perennials 212

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °FAmerican bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °FAmerican licorice4 ft · blooms late spring · medium shade tolerance · to −38 °FAmerican lotus3 ft · blooms mid summer · high shade tolerance · to −36 °FAmerican pokeweed7 ft · blooms mid summer · low shade tolerance · to −33 °F

Grasses 181

American beachgrass2.5 ft · blooms spring · high shade tolerance · to −28 °Farctic brome3 ft · blooms early summer · low shade tolerance · to −33 °FAtlantic mannagrass3 ft · blooms summer · low shade tolerance · to −8 °Fautumn bluegrass1.5 ft · blooms late spring · medium shade tolerance · to −8 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °FBailey's sedge2.1 ft · blooms late spring · low shade tolerance · to −33 °F

Vines 11

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °FAmerican wisteria50 ft · blooms spring · low shade tolerance · to −3 °Fdevil's darning needles15 ft · blooms mid summer · medium shade tolerance · to −38 °Ffrost grape83 ft · blooms late spring · medium shade tolerance · to −23 °Fgraybark grape50 ft · blooms late spring · medium shade tolerance · to −8 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °F

Source: USDA, NRCS. 2026. The PLANTS Database (plants.usda.gov), National Plant Data Team — state distribution, native status and the “Temperature, Minimum” characteristic. Check light, moisture and soil needs before buying; local nurseries and your state native plant society can confirm what thrives in Valley Forge, PA.

Soil in Valley Forge, PA

The soil mapped at the center of ZIP 19494 is Edgemont — channery loam, well drained.

TextureChannery loama good balance for most vegetables
pH6.1slightly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter3%moderate
Hydrologic groupAwater soaks in fast
Farmland classNot prime farmlandUSDA classification

Map unit: Edgemont channery loam, 15 to 25 percent slopes.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 19494; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Valley Forge, PA

Summer high88 °Faverage high, July
Winter low23 °Faverage low, January
Hot days29days a year at 90 °F or more
Freezing nights117nights a year at 32 °F or less
Growing degree days3,668base 50 °F — the season’s usable heat
Longest day15 h 02 mindaylight on June 21
Shortest day9 h 19 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation45.1 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 41 °F, low 23 °F 41°23° JanFebruary: average high 44 °F, low 24 °F 44°24° FebMarch: average high 53 °F, low 31 °F 53°31° MarApril: average high 65 °F, low 41 °F 65°41° AprMay: average high 75 °F, low 51 °F 75°51° MayJune: average high 83 °F, low 61 °F 83°61° JunJuly: average high 88 °F, low 66 °F 88°66° JulAugust: average high 86 °F, low 64 °F 86°64° AugSeptember: average high 79 °F, low 56 °F 79°56° SepOctober: average high 67 °F, low 44 °F 67°44° OctNovember: average high 56 °F, low 34 °F 56°34° NovDecember: average high 45 °F, low 27 °F 45°27° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 3.15 in precipitation 3.1 JanFebruary: 2.87 in precipitation 2.9 FebMarch: 3.67 in precipitation 3.7 MarApril: 3.52 in precipitation 3.5 AprMay: 3.30 in precipitation 3.3 MayJune: 3.85 in precipitation 3.9 JunJuly: 4.57 in precipitation 4.6 JulAugust: 4.37 in precipitation 4.4 AugSeptember: 4.43 in precipitation 4.4 SepOctober: 3.91 in precipitation 3.9 OctNovember: 3.41 in precipitation 3.4 NovDecember: 4.08 in precipitation 4.1 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Phoenixville 1 E, PA (2 mi away); precipitation: Phoenixville 1 E, PA (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 7a.

194937a
Valley Forge, PA · <1 mi
194957a
Valley Forge, PA · <1 mi
194967a
Valley Forge, PA · <1 mi
194817a
Valley Forge, PA · <1 mi
194827a
Valley Forge, PA · 1 mi
194537a
Mont Clare, PA · 3 mi
194607a
Phoenixville, PA · 4 mi
193017a
Paoli, PA · 4 mi

All 7 ZIP codes in Valley Forge → · Pennsylvania planting zones →

Questions about 19494

What planting zone is ZIP code 19494?

ZIP code 19494 (Valley Forge, PA) is in USDA hardiness zone 7a on the 2023 map: the coldest night of an average winter reaches 0 to 5 °F (−17.8 to −15 °C).

When is the last frost in Valley Forge, PA?

The median last spring frost (32 °F) near 19494 is April 18; after May 4 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Phoenixville 1 E station.

When is the first frost in Valley Forge, PA?

The median first fall frost near 19494 is October 27, giving a median frost-free growing season of 192 days.

When should I plant tomatoes in 19494?

Start tomato seeds indoors around Feb 21 – Mar 7 and set transplants outside around Apr 25 – May 9, one to three weeks after the median last frost.

How much rain and snow does 19494 get?

About 45.1 inches of precipitation a year (NOAA 1991–2020 normals, Phoenixville 1 E station).

How hot do summers get in Valley Forge, PA?

The average high peaks at 88 °F in July, with about 29 days a year at 90 °F or more.

What kind of soil does 19494 have?

The USDA soil survey maps Edgemont at the center of ZIP 19494: channery loam, well drained, pH about 6.1 (slightly acidic).

Did spring come early in Valley Forge, PA in 2026?

Spring leaf-out near 19494 came on Mar 22 in 2026, 3 days earlier than the 1991–2020 average (Mar 25), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Valley Forge, PA?

Long-day onions: the longest day near 19494 is 15 h 02 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 19494 change?

Yes. The 2012 USDA map put 19494 in zone 6b; the 2023 map puts it in zone 7a. The newer map uses 1991–2020 data and more weather stations.