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

Planting zone for 17059 — Mifflintown, PA

ZIP code 17059 (Mifflintown, Juniata County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 21 and the first fall frost October 24.

Where ZIP 17059 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 21
First frostOct 24
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 Mifflintown, 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 Mifflintown, PA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 21median — 50% chance of a later frost
Safe for tender plantsMay 9only 10% chance of frost after
First fall frostOctober 24median — 10% chance by Oct 7
Growing season185 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 6 and returns around November 5.

From the NOAA station Lewistown, PA — 9 miles away, elevation 459 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 17059

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 10 – Mar 24
SpinachSow outdoors · Mar 10 – Mar 31
Broccoli, cabbageStart indoors · Feb 10 – Feb 24
Broccoli, cabbageTransplant · Mar 31 – Apr 14
Onion setsPlant outdoors · Mar 24 – Apr 7
PotatoesPlant outdoors · Mar 31 – Apr 14
LettuceSow outdoors · Mar 24 – Apr 7
Carrots, beetsSow outdoors · Mar 31 – Apr 14
TomatoesStart indoors · Feb 24 – Mar 10
TomatoesTransplant · Apr 28 – May 12
Peppers, eggplantStart indoors · Feb 10 – Feb 24
Peppers, eggplantTransplant · May 5 – May 19
BeansSow outdoors · Apr 28 – May 12
Sweet cornSow outdoors · Apr 28 – May 12
Cucumbers, squashSow outdoors · Apr 28 – May 12
Fall lettuce, spinachSow outdoors · Aug 29 – Sep 12
GarlicPlant cloves · Oct 10 – Nov 14
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 21) and first fall frost (Oct 24) 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 17059 came on Mar 22 — 12 days earlier than the 1991–2020 average (Apr 3).

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 Mifflintown, PA.

Soil in Mifflintown, PA

The soil mapped at the center of ZIP 17059 is Morrison — gravelly sandy loam, well drained.

TextureGravelly sandy loamdrains and warms fast; dries out and needs more feeding
pH4.6strongly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter2.5%moderate
Hydrologic groupAwater soaks in fast
Farmland classprime farmlandUSDA classification

Map unit: Morrison gravelly sandy 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 17059; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Mifflintown, PA

Summer high85 °Faverage high, July
Winter low21 °Faverage low, January
Hot days18days a year at 90 °F or more
Freezing nights122nights a year at 32 °F or less
Growing degree days3,165base 50 °F — the season’s usable heat
Longest day15 h 05 mindaylight on June 21
Shortest day9 h 16 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation42.1 inper year, rain and melted snow
Snowfall26 inper year; 30 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 40 °F, low 22 °F 40°22° FebMarch: average high 49 °F, low 29 °F 49°29° MarApril: average high 63 °F, low 39 °F 63°39° AprMay: average high 73 °F, low 49 °F 73°49° MayJune: average high 81 °F, low 58 °F 81°58° JunJuly: average high 85 °F, low 63 °F 85°63° JulAugust: average high 84 °F, low 61 °F 84°61° AugSeptember: average high 77 °F, low 54 °F 77°54° SepOctober: average high 65 °F, low 43 °F 65°43° OctNovember: average high 53 °F, low 33 °F 53°33° NovDecember: average high 41 °F, low 26 °F 41°26° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 2.89 in precipitation, 9.1 in snowfall 2.9❄9 JanFebruary: 2.31 in precipitation, 6.9 in snowfall 2.3❄7 FebMarch: 3.57 in precipitation, 4.3 in snowfall 3.6❄4 MarApril: 3.53 in precipitation, 0.2 in snowfall 3.5 AprMay: 4.16 in precipitation 4.2 MayJune: 3.95 in precipitation 4.0 JunJuly: 3.64 in precipitation 3.6 JulAugust: 3.61 in precipitation 3.6 AugSeptember: 4.40 in precipitation 4.4 SepOctober: 3.75 in precipitation, 0.1 in snowfall 3.8 OctNovember: 3.06 in precipitation, 0.9 in snowfall 3.1❄1 NovDecember: 3.27 in precipitation, 4.7 in snowfall 3.3❄5 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Lewistown, PA (9 mi away); precipitation: Lewistown, PA (9 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

3 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

170567a
Mexico, PA · 4 mi
170827a
Port Royal, PA · 7 mi
170496b
Mc Alisterville, PA · 8 mi
170946b
Thompsontown, PA · 9 mi
178416b
Mc Clure, PA · 10 mi
170097a
Burnham, PA · 10 mi
170587a
Mifflin, PA · 10 mi
170997a
Yeagertown, PA · 10 mi

Pennsylvania planting zones →

Questions about 17059

What planting zone is ZIP code 17059?

ZIP code 17059 (Mifflintown, 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 Mifflintown, PA?

The median last spring frost (32 °F) near 17059 is April 21; after May 9 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Lewistown station.

When is the first frost in Mifflintown, PA?

The median first fall frost near 17059 is October 24, giving a median frost-free growing season of 185 days.

When should I plant tomatoes in 17059?

Start tomato seeds indoors around Feb 24 – Mar 10 and set transplants outside around Apr 28 – May 12, one to three weeks after the median last frost.

How much rain and snow does 17059 get?

About 42.1 inches of precipitation a year and 26 inches of snowfall (NOAA 1991–2020 normals, Lewistown station).

How hot do summers get in Mifflintown, PA?

The average high peaks at 85 °F in July, with about 18 days a year at 90 °F or more.

What kind of soil does 17059 have?

The USDA soil survey maps Morrison at the center of ZIP 17059: gravelly sandy loam, well drained, pH about 4.6 (strongly acidic).

Did spring come early in Mifflintown, PA in 2026?

Spring leaf-out near 17059 came on Mar 22 in 2026, 12 days earlier than the 1991–2020 average (Apr 3), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Mifflintown, PA?

Long-day onions: the longest day near 17059 is 15 h 05 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 17059 change?

Yes. The 2012 USDA map put 17059 in zone 6b; the 2023 map puts it in zone 7a. The newer map uses 1991–2020 data and more weather stations.