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

Planting zone for 17555 — Narvon, PA

ZIP code 17555 (Narvon, Lancaster County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 16 and the first fall frost October 27.

Where ZIP 17555 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 16
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 Narvon, 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 Narvon, PA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 16median — 50% chance of a later frost
Safe for tender plantsApril 30only 10% chance of frost after
First fall frostOctober 27median — 10% chance by Oct 11
Growing season193 daysfrost-free, median

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

From the NOAA station Hopewell Morgantown, PA — 4 miles away, elevation 551 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 17555

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 5 – Mar 19
SpinachSow outdoors · Mar 5 – Mar 26
Broccoli, cabbageStart indoors · Feb 5 – Feb 19
Broccoli, cabbageTransplant · Mar 26 – Apr 9
Onion setsPlant outdoors · Mar 19 – Apr 2
PotatoesPlant outdoors · Mar 26 – Apr 9
LettuceSow outdoors · Mar 19 – Apr 2
Carrots, beetsSow outdoors · Mar 26 – Apr 9
TomatoesStart indoors · Feb 19 – Mar 5
TomatoesTransplant · Apr 23 – May 7
Peppers, eggplantStart indoors · Feb 5 – Feb 19
Peppers, eggplantTransplant · Apr 30 – May 14
BeansSow outdoors · Apr 23 – May 7
Sweet cornSow outdoors · Apr 23 – May 7
Cucumbers, squashSow outdoors · Apr 23 – May 7
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 16) 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 17555 came on Mar 22 — 6 days earlier than the 1991–2020 average (Mar 28).

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).

Soil in Narvon, PA

The soil mapped at the center of ZIP 17555 is Chester — silt loam, well drained.

TextureSilt loama good balance for most vegetables
pH5.0strongly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter3.25%moderate
Hydrologic groupBwater soaks in moderately
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Chester silt loam, 8 to 15 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 17555; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Narvon, PA

Summer high85 °Faverage high, July
Winter low21 °Faverage low, January
Hot days12days a year at 90 °F or more
Freezing nights121nights a year at 32 °F or less
Growing degree days3,152base 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)
Precipitation47 inper year, rain and melted snow
Snowfall23 inper year; 27 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 37 °F, low 21 °F 37°21° JanFebruary: average high 41 °F, low 22 °F 41°22° FebMarch: average high 49 °F, low 31 °F 49°31° MarApril: average high 62 °F, low 39 °F 62°39° 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 82 °F, low 62 °F 82°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 34 °F 53°34° NovDecember: average high 42 °F, low 27 °F 42°27° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 3.20 in precipitation, 5.8 in snowfall 3.2❄6 JanFebruary: 2.43 in precipitation, 8.8 in snowfall 2.4❄9 FebMarch: 3.98 in precipitation, 3.7 in snowfall 4.0❄4 MarApril: 3.58 in precipitation, 0.4 in snowfall 3.6 AprMay: 3.63 in precipitation 3.6 MayJune: 4.58 in precipitation 4.6 JunJuly: 4.58 in precipitation 4.6 JulAugust: 4.47 in precipitation 4.5 AugSeptember: 4.69 in precipitation 4.7 SepOctober: 4.46 in precipitation, 0.4 in snowfall 4.5 OctNovember: 3.25 in precipitation, 0.6 in snowfall 3.3❄1 NovDecember: 4.10 in precipitation, 3.6 in snowfall 4.1❄4 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Hopewell Morgantown, PA (4 mi away); precipitation: Honey Brook 2 Sse, PA (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 7a.

175287a
Goodville, PA · 2 mi
175197a
East Earl, PA · 4 mi
193717a
Suplee, PA · 5 mi
193447a
Honey Brook, PA · 5 mi
175067a
Blue Ball, PA · 5 mi
195437a
Morgantown, PA · 5 mi
175817a
Terre Hill, PA · 6 mi
175077a
Bowmansville, PA · 6 mi

Pennsylvania planting zones →

Questions about 17555

What planting zone is ZIP code 17555?

ZIP code 17555 (Narvon, 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 Narvon, PA?

The median last spring frost (32 °F) near 17555 is April 16; after April 30 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Hopewell Morgantown station.

When is the first frost in Narvon, PA?

The median first fall frost near 17555 is October 27, giving a median frost-free growing season of 193 days.

When should I plant tomatoes in 17555?

Start tomato seeds indoors around Feb 19 – Mar 5 and set transplants outside around Apr 23 – May 7, one to three weeks after the median last frost.

How much rain and snow does 17555 get?

About 47 inches of precipitation a year and 23 inches of snowfall (NOAA 1991–2020 normals, Honey Brook 2 Sse station).

How hot do summers get in Narvon, PA?

The average high peaks at 85 °F in July, with about 12 days a year at 90 °F or more.

What kind of soil does 17555 have?

The USDA soil survey maps Chester at the center of ZIP 17555: silt loam, well drained, pH about 5.0 (strongly acidic).

Did spring come early in Narvon, PA in 2026?

Spring leaf-out near 17555 came on Mar 22 in 2026, 6 days earlier than the 1991–2020 average (Mar 28), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Narvon, PA?

Long-day onions: the longest day near 17555 is 15 h 02 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 17555 change?

Yes. The 2012 USDA map put 17555 in zone 6b; the 2023 map puts it in zone 7a. The newer map uses 1991–2020 data and more weather stations.