Planting zone for 57341 — Gann Valley, SD
ZIP code 57341 (Gann Valley, Buffalo County) is in USDA zone 4b: the coldest winter night averages −25 to −20 °F. The median last spring frost is May 6 and the first fall frost October 1.
Where ZIP 57341 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.
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 4b means →
Frost forecast — next 7 nights
live from the National Weather ServiceLoading the forecast for Gann Valley, SD…
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 Gann Valley, SD
A hard freeze (28 °F) usually ends around April 28 and returns around October 9.
From the NOAA station Gann Valley 4nw, SD — 4 miles away, elevation 1,719 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 57341
Counted from the median last spring frost (May 6) and first fall frost (Oct 1) 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 57341 came on Mar 24 — 19 days earlier than the 1991–2020 average (Apr 12).
Apr 122026
Mar 24
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 4b in South Dakota
430 plants native to the lower 48 states, recorded in South Dakota, and rated by the USDA to survive −25 °F or colder — the bottom of zone 4b. Each links to its USDA PLANTS profile.
Trees 23
Shrubs 65
Wildflowers & perennials 191
Grasses 138
Vines 5
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 Gann Valley, SD.
Soil in Gann Valley, SD
The soil mapped at the center of ZIP 57341 is Betts — loam, well drained.
Map unit: Betts-Java loams, 20 to 40 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 57341; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.
Climate in Gann Valley, SD
Average high and low, by month
Precipitation by month inches · ❄ = snowfall
NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Gann Valley 4nw, SD (4 mi away); precipitation: Gann Valley 3 Nne, SD (7 mi away). Daylight is calculated from latitude.
Nearby ZIP codes
5 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.
Questions about 57341
What planting zone is ZIP code 57341?
ZIP code 57341 (Gann Valley, SD) is in USDA hardiness zone 4b on the 2023 map: the coldest night of an average winter reaches −25 to −20 °F (−31.7 to −28.9 °C).
When is the last frost in Gann Valley, SD?
The median last spring frost (32 °F) near 57341 is May 6; after May 19 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Gann Valley 4nw station.
When is the first frost in Gann Valley, SD?
The median first fall frost near 57341 is October 1, giving a median frost-free growing season of 148 days.
When should I plant tomatoes in 57341?
Start tomato seeds indoors around Mar 11 – Mar 25 and set transplants outside around May 13 – May 27, one to three weeks after the median last frost.
How much rain and snow does 57341 get?
About 22.7 inches of precipitation a year and 41 inches of snowfall (NOAA 1991–2020 normals, Gann Valley 3 Nne station).
How hot do summers get in Gann Valley, SD?
The average high peaks at 87 °F in July, with about 27 days a year at 90 °F or more.
What kind of soil does 57341 have?
The USDA soil survey maps Betts at the center of ZIP 57341: loam, well drained, pH about 7.7 (slightly alkaline).
Did spring come early in Gann Valley, SD in 2026?
Spring leaf-out near 57341 came on Mar 24 in 2026, 19 days earlier than the 1991–2020 average (Apr 12), according to the USA National Phenology Network Spring Index.
What kind of onions grow in Gann Valley, SD?
Long-day onions: the longest day near 57341 is 15 h 30 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).