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

Planting zone for 19335 — Downingtown, PA

ZIP code 19335 (Downingtown, Chester County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 11 and the first fall frost November 1.

Where ZIP 19335 is

Outlined: the ZIP code area · 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 11
First frostNov 1
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 Downingtown, 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 Downingtown, PA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 11median — 50% chance of a later frost
Safe for tender plantsApril 29only 10% chance of frost after
First fall frostNovember 1median — 10% chance by Oct 16
Growing season205 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 31 and returns around November 15.

From the NOAA station Glenmoore, PA — 6 miles away, elevation 499 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 19335

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Feb 28 – Mar 14
SpinachSow outdoors · Feb 28 – Mar 21
Broccoli, cabbageStart indoors · Jan 31 – Feb 14
Broccoli, cabbageTransplant · Mar 21 – Apr 4
Onion setsPlant outdoors · Mar 14 – Mar 28
PotatoesPlant outdoors · Mar 21 – Apr 4
LettuceSow outdoors · Mar 14 – Mar 28
Carrots, beetsSow outdoors · Mar 21 – Apr 4
TomatoesStart indoors · Feb 14 – Feb 28
TomatoesTransplant · Apr 18 – May 2
Peppers, eggplantStart indoors · Jan 31 – Feb 14
Peppers, eggplantTransplant · Apr 25 – May 9
BeansSow outdoors · Apr 18 – May 2
Sweet cornSow outdoors · Apr 18 – May 2
Cucumbers, squashSow outdoors · Apr 18 – May 2
Fall lettuce, spinachSow outdoors · Sep 6 – Sep 20
GarlicPlant cloves · Oct 18 – Nov 22
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 11) and first fall frost (Nov 1) 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 19335 came on Mar 24 — 3 days earlier than the 1991–2020 average (Mar 27).

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

Shrubs 123

Wildflowers & perennials 212

Grasses 181

Vines 11

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 Downingtown, PA.

Soil in Downingtown, PA

The soil mapped at the center of ZIP 19335 is Udorthents — loam, well drained. Much of the area is built over (urban land); this is the natural soil underneath.

TextureLoama good balance for most vegetables
pH5.8moderately acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter1.5%low — add compost
Hydrologic groupCwater soaks in slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Urban land-Udorthents, schist and gneiss complex, 0 to 8 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 19335; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Downingtown, PA

Summer high85 °Faverage high, July
Winter low23 °Faverage low, January
Hot days16days a year at 90 °F or more
Freezing nights107nights a year at 32 °F or less
Growing degree days3,245base 50 °F — the season’s usable heat
Longest day15 h 01 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)
Precipitation50.8 inper year, rain and melted snow
Snowfall28 inper year; 31 days with snow on the ground

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 38 °F, low 23 °F 38°23° JanFebruary: average high 41 °F, low 23 °F 41°23° FebMarch: average high 49 °F, low 30 °F 49°30° MarApril: average high 62 °F, low 40 °F 62°40° AprMay: average high 72 °F, low 50 °F 72°50° MayJune: average high 80 °F, low 59 °F 80°59° JunJuly: average high 85 °F, low 64 °F 85°64° JulAugust: average high 83 °F, low 62 °F 83°62° AugSeptember: average high 76 °F, low 55 °F 76°55° SepOctober: average high 64 °F, low 44 °F 64°44° OctNovember: average high 53 °F, low 35 °F 53°35° NovDecember: average high 43 °F, low 28 °F 43°28° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 3.72 in precipitation, 8.9 in snowfall 3.7❄9 JanFebruary: 3.19 in precipitation, 9.5 in snowfall 3.2❄10 FebMarch: 4.49 in precipitation, 4 in snowfall 4.5❄4 MarApril: 4.02 in precipitation, 1 in snowfall 4.0❄1 AprMay: 4.03 in precipitation 4.0 MayJune: 4.62 in precipitation 4.6 JunJuly: 4.84 in precipitation 4.8 JulAugust: 4.63 in precipitation 4.6 AugSeptember: 4.86 in precipitation 4.9 SepOctober: 4.54 in precipitation, 0.2 in snowfall 4.5 OctNovember: 3.40 in precipitation, 0.9 in snowfall 3.4❄1 NovDecember: 4.48 in precipitation, 3.9 in snowfall 4.5❄4 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Glenmoore, PA (6 mi away); precipitation: Glenmoore, PA (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 7a.

Pennsylvania planting zones →

Questions about 19335

What planting zone is ZIP code 19335?

ZIP code 19335 (Downingtown, 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 Downingtown, PA?

The median last spring frost (32 °F) near 19335 is April 11; after April 29 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Glenmoore station.

When is the first frost in Downingtown, PA?

The median first fall frost near 19335 is November 1, giving a median frost-free growing season of 205 days.

When should I plant tomatoes in 19335?

Start tomato seeds indoors around Feb 14 – Feb 28 and set transplants outside around Apr 18 – May 2, one to three weeks after the median last frost.

How much rain and snow does 19335 get?

About 50.8 inches of precipitation a year and 28 inches of snowfall (NOAA 1991–2020 normals, Glenmoore station).

How hot do summers get in Downingtown, PA?

The average high peaks at 85 °F in July, with about 16 days a year at 90 °F or more.

What kind of soil does 19335 have?

The USDA soil survey maps Udorthents at the center of ZIP 19335: loam, well drained, pH about 5.8 (moderately acidic).

Did spring come early in Downingtown, PA in 2026?

Spring leaf-out near 19335 came on Mar 24 in 2026, 3 days earlier than the 1991–2020 average (Mar 27), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Downingtown, PA?

Long-day onions: the longest day near 19335 is 15 h 01 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 19335 change?

Yes. The 2012 USDA map put 19335 in zone 6b; the 2023 map puts it in zone 7a. The newer map uses 1991–2020 data and more weather stations.