Planting zone for 15730 — Coolspring, PA
ZIP code 15730 (Coolspring, Jefferson County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is May 10 and the first fall frost October 12.
Where ZIP 15730 is
Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoomNot 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.
Was 5b 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 6a means →
Frost forecast — next 7 nights
live from the National Weather ServiceLoading the forecast for Coolspring, 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 Coolspring, PA
A hard freeze (28 °F) usually ends around April 28 and returns around October 26.
From the NOAA station Putneyville 2 Se Dam, PA — 12 miles away, elevation 1,280 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 15730
Counted from the median last spring frost (May 10) and first fall frost (Oct 12) 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 15730 came on Mar 21 — 17 days earlier than the 1991–2020 average (Apr 7).
Apr 72026
Mar 21
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 Coolspring, PA
The soil mapped at the center of ZIP 15730 is Gilpin — channery silt loam, well drained.
Map unit: Gilpin channery silt loam, 25 to 60 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 15730; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.
Climate in Coolspring, PA
Average high and low, by month
Precipitation by month inches
NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Putneyville 2 Se Dam, PA (12 mi away); precipitation: Brookville 5.3 Ssw, PA (4 mi away). Daylight is calculated from latitude.
Nearby ZIP codes
All 8 nearest ZIP codes share zone 6a.
Questions about 15730
What planting zone is ZIP code 15730?
ZIP code 15730 (Coolspring, PA) is in USDA hardiness zone 6a on the 2023 map: the coldest night of an average winter reaches −10 to −5 °F (−23.3 to −20.6 °C).
When is the last frost in Coolspring, PA?
The median last spring frost (32 °F) near 15730 is May 10; after May 28 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Putneyville 2 Se Dam station.
When is the first frost in Coolspring, PA?
The median first fall frost near 15730 is October 12, giving a median frost-free growing season of 155 days.
When should I plant tomatoes in 15730?
Start tomato seeds indoors around Mar 15 – Mar 29 and set transplants outside around May 17 – May 31, one to three weeks after the median last frost.
How much rain and snow does 15730 get?
About 45.7 inches of precipitation a year (NOAA 1991–2020 normals, Brookville 5.3 Ssw station).
How hot do summers get in Coolspring, PA?
The average high peaks at 82 °F in July, with about 7 days a year at 90 °F or more.
What kind of soil does 15730 have?
The USDA soil survey maps Gilpin at the center of ZIP 15730: channery silt loam, well drained, pH about 5.8 (moderately acidic).
Did spring come early in Coolspring, PA in 2026?
Spring leaf-out near 15730 came on Mar 21 in 2026, 17 days earlier than the 1991–2020 average (Apr 7), according to the USA National Phenology Network Spring Index.
What kind of onions grow in Coolspring, PA?
Long-day onions: the longest day near 15730 is 15 h 08 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).
Did the zone for 15730 change?
Yes. The 2012 USDA map put 15730 in zone 5b; the 2023 map puts it in zone 6a. The newer map uses 1991–2020 data and more weather stations.