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

Planting zone for 17837 — Lewisburg, PA

ZIP code 17837 (Lewisburg, Union County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 26 and the first fall frost October 20.

Where ZIP 17837 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.

Zone6b−5 to 0 °F
Coldest night−20.6 to −17.8 °C
Last frostApr 26
First frostOct 20
2012 zone6b

Same zone as on the 2012 map. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Lewisburg, 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 Lewisburg, PA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 26median — 50% chance of a later frost
Safe for tender plantsMay 11only 10% chance of frost after
First fall frostOctober 20median — 10% chance by Oct 5
Growing season176 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 14 and returns around November 1.

From the NOAA station Lewisburg, PA — 4 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 17837

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 15 – Mar 29
SpinachSow outdoors · Mar 15 – Apr 5
Broccoli, cabbageStart indoors · Feb 15 – Mar 1
Broccoli, cabbageTransplant · Apr 5 – Apr 19
Onion setsPlant outdoors · Mar 29 – Apr 12
PotatoesPlant outdoors · Apr 5 – Apr 19
LettuceSow outdoors · Mar 29 – Apr 12
Carrots, beetsSow outdoors · Apr 5 – Apr 19
TomatoesStart indoors · Mar 1 – Mar 15
TomatoesTransplant · May 3 – May 17
Peppers, eggplantStart indoors · Feb 15 – Mar 1
Peppers, eggplantTransplant · May 10 – May 24
BeansSow outdoors · May 3 – May 17
Sweet cornSow outdoors · May 3 – May 17
Cucumbers, squashSow outdoors · May 3 – May 17
Fall lettuce, spinachSow outdoors · Aug 25 – Sep 8
GarlicPlant cloves · Oct 6 – Nov 10
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 26) and first fall frost (Oct 20) 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 17837 came on Mar 31 — 4 days earlier than the 1991–2020 average (Apr 4).

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 Lewisburg, PA

The soil mapped at the center of ZIP 17837 is Opequon — silty clay loam, well drained.

TextureSilty clay loamholds water and nutrients; slow to drain and warm up
pH6.1slightly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter2.29%moderate
Hydrologic groupDwater soaks in very slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Opequon silty clay loam, 8 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 17837; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Lewisburg, PA

Summer high84 °Faverage high, July
Winter low19 °Faverage low, January
Hot days13days a year at 90 °F or more
Freezing nights133nights a year at 32 °F or less
Growing degree days2,923base 50 °F — the season’s usable heat
Longest day15 h 07 mindaylight on June 21
Shortest day9 h 13 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation43.9 inper year, rain and melted snow
Snowfall29 inper year; 37 days with snow on the ground

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 35 °F, low 19 °F 35°19° JanFebruary: average high 38 °F, low 20 °F 38°20° FebMarch: average high 48 °F, low 27 °F 48°27° MarApril: average high 62 °F, low 37 °F 62°37° AprMay: average high 72 °F, low 48 °F 72°48° MayJune: average high 80 °F, low 57 °F 80°57° JunJuly: average high 84 °F, low 62 °F 84°62° JulAugust: average high 83 °F, low 60 °F 83°60° AugSeptember: average high 75 °F, low 52 °F 75°52° SepOctober: average high 63 °F, low 41 °F 63°41° OctNovember: average high 51 °F, low 31 °F 51°31° NovDecember: average high 40 °F, low 24 °F 40°24° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 3.13 in precipitation, 8 in snowfall 3.1❄8 JanFebruary: 2.41 in precipitation, 7.8 in snowfall 2.4❄8 FebMarch: 3.48 in precipitation, 5.3 in snowfall 3.5❄5 MarApril: 3.75 in precipitation, 0.8 in snowfall 3.8❄1 AprMay: 3.93 in precipitation 3.9 MayJune: 3.74 in precipitation 3.7 JunJuly: 4.49 in precipitation 4.5 JulAugust: 4.28 in precipitation 4.3 AugSeptember: 4.41 in precipitation 4.4 SepOctober: 3.81 in precipitation, 0.2 in snowfall 3.8 OctNovember: 3.10 in precipitation, 1.3 in snowfall 3.1❄1 NovDecember: 3.35 in precipitation, 5.4 in snowfall 3.4❄5 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Lewisburg, PA (4 mi away); precipitation: Lewisburg, PA (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6b.

178506b
Montandon, PA · 5 mi
178866b
West Milton, PA · 5 mi
178566b
New Columbia, PA · 6 mi
178556b
New Berlin, PA · 6 mi
178896b
Winfield, PA · 7 mi
178476b
Milton, PA · 7 mi
178446b
Mifflinburg, PA · 7 mi
178876b
White Deer, PA · 7 mi

Pennsylvania planting zones →

Questions about 17837

What planting zone is ZIP code 17837?

ZIP code 17837 (Lewisburg, PA) is in USDA hardiness zone 6b on the 2023 map: the coldest night of an average winter reaches −5 to 0 °F (−20.6 to −17.8 °C).

When is the last frost in Lewisburg, PA?

The median last spring frost (32 °F) near 17837 is April 26; after May 11 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Lewisburg station.

When is the first frost in Lewisburg, PA?

The median first fall frost near 17837 is October 20, giving a median frost-free growing season of 176 days.

When should I plant tomatoes in 17837?

Start tomato seeds indoors around Mar 1 – Mar 15 and set transplants outside around May 3 – May 17, one to three weeks after the median last frost.

How much rain and snow does 17837 get?

About 43.9 inches of precipitation a year and 29 inches of snowfall (NOAA 1991–2020 normals, Lewisburg station).

How hot do summers get in Lewisburg, PA?

The average high peaks at 84 °F in July, with about 13 days a year at 90 °F or more.

What kind of soil does 17837 have?

The USDA soil survey maps Opequon at the center of ZIP 17837: silty clay loam, well drained, pH about 6.1 (slightly acidic).

Did spring come early in Lewisburg, PA in 2026?

Spring leaf-out near 17837 came on Mar 31 in 2026, 4 days earlier than the 1991–2020 average (Apr 4), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Lewisburg, PA?

Long-day onions: the longest day near 17837 is 15 h 07 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).