Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 17050 — Mechanicsburg, PA

ZIP code 17050 (Mechanicsburg, Cumberland County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 23 and the first fall frost October 18.

Where ZIP 17050 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 23

First frostOct 18

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 Mechanicsburg, 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 Mechanicsburg, PA

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostApril 23median — 50% chance of a later frost

Safe for tender plantsMay 9only 10% chance of frost after

First fall frostOctober 18median — 10% chance by Oct 4

Growing season177 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 10 and returns around November 1.

From the NOAA station Carlisle Wtp, PA — 9 miles away, elevation 430 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 17050

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 12 – Mar 26

SpinachSow outdoors · Mar 12 – Apr 2

Broccoli, cabbageStart indoors · Feb 12 – Feb 26

Broccoli, cabbageTransplant · Apr 2 – Apr 16

Onion setsPlant outdoors · Mar 26 – Apr 9

PotatoesPlant outdoors · Apr 2 – Apr 16

LettuceSow outdoors · Mar 26 – Apr 9

Carrots, beetsSow outdoors · Apr 2 – Apr 16

TomatoesStart indoors · Feb 26 – Mar 12

TomatoesTransplant · Apr 30 – May 14

Peppers, eggplantStart indoors · Feb 12 – Feb 26

Peppers, eggplantTransplant · May 7 – May 21

BeansSow outdoors · Apr 30 – May 14

Sweet cornSow outdoors · Apr 30 – May 14

Cucumbers, squashSow outdoors · Apr 30 – May 14

Fall lettuce, spinachSow outdoors · Aug 23 – Sep 6

GarlicPlant cloves · Oct 4 – Nov 8

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 23) and first fall frost (Oct 18) 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 17050 came on Mar 21 — 7 days earlier than the 1991–2020 average (Mar 28).

average
Mar 282026
Mar 21

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.

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 Mechanicsburg, PA.

Soil in Mechanicsburg, PA

The soil mapped at the center of ZIP 17050 is Hagerstown — silt loam, well drained.

TextureSilt loama good balance for most vegetables

pH6.0slightly acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter3%moderate

Hydrologic groupBwater soaks in moderately

Farmland classprime farmlandUSDA classification

Map unit: Hagerstown silt loam, 3 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 17050; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Mechanicsburg, PA

Summer high86 °Faverage high, July

Winter low21 °Faverage low, January

Hot days24days a year at 90 °F or more

Freezing nights127nights a year at 32 °F or less

Growing degree days3,156base 50 °F — the season’s usable heat

Longest day15 h 03 mindaylight on June 21

Shortest day9 h 18 mindaylight on December 21

Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)

Precipitation45.6 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Carlisle Wtp, PA (9 mi away); precipitation: Mechanicsburg 1.0 Nnw, PA (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 7a.

170727a

New Kingstown, PA · 3 mi

170257a

Enola, PA · 4 mi

170557a

Mechanicsburg, PA · 5 mi

170897a

Camp Hill, PA · 5 mi

170537a

Marysville, PA · 5 mi

All 2 ZIP codes in Mechanicsburg → · Pennsylvania planting zones →

Questions about 17050

What planting zone is ZIP code 17050?

ZIP code 17050 (Mechanicsburg, 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 Mechanicsburg, PA?

The median last spring frost (32 °F) near 17050 is April 23; after May 9 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Carlisle Wtp station.

When is the first frost in Mechanicsburg, PA?

The median first fall frost near 17050 is October 18, giving a median frost-free growing season of 177 days.

When should I plant tomatoes in 17050?

Start tomato seeds indoors around Feb 26 – Mar 12 and set transplants outside around Apr 30 – May 14, one to three weeks after the median last frost.

How much rain and snow does 17050 get?

About 45.6 inches of precipitation a year (NOAA 1991–2020 normals, Mechanicsburg 1.0 Nnw station).

How hot do summers get in Mechanicsburg, PA?

The average high peaks at 86 °F in July, with about 24 days a year at 90 °F or more.

What kind of soil does 17050 have?

The USDA soil survey maps Hagerstown at the center of ZIP 17050: silt loam, well drained, pH about 6.0 (slightly acidic).

Did spring come early in Mechanicsburg, PA in 2026?

Spring leaf-out near 17050 came on Mar 21 in 2026, 7 days earlier than the 1991–2020 average (Mar 28), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Mechanicsburg, PA?

Long-day onions: the longest day near 17050 is 15 h 03 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 17050 change?

Yes. The 2012 USDA map put 17050 in zone 6b; the 2023 map puts it in zone 7a. The newer map uses 1991–2020 data and more weather stations.