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

Planting zone for 58310 — Agate, ND

ZIP code 58310 (Agate, Rolette County) is in USDA zone 3b: the coldest winter night averages −35 to −30 °F. The median last spring frost is May 22 and the first fall frost September 20.

Where ZIP 58310 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.

Zone3b−35 to −30 °F

Coldest night−37.2 to −34.4 °C

Last frostMay 22

First frostSep 20

2012 zone3b

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 3b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Agate, ND…

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 Agate, ND

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMay 22median — 50% chance of a later frost

Safe for tender plantsJune 3only 10% chance of frost after

First fall frostSeptember 20median — 10% chance by Sep 5

Growing season120 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 13 and returns around September 27.

From the NOAA station Rolette 3se, ND — 12 miles away, elevation 1,621 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 58310

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 10 – Apr 24

SpinachSow outdoors · Apr 10 – May 1

Broccoli, cabbageStart indoors · Mar 13 – Mar 27

Broccoli, cabbageTransplant · May 1 – May 15

Onion setsPlant outdoors · Apr 24 – May 8

PotatoesPlant outdoors · May 1 – May 15

LettuceSow outdoors · Apr 24 – May 8

Carrots, beetsSow outdoors · May 1 – May 15

TomatoesStart indoors · Mar 27 – Apr 10

TomatoesTransplant · May 29 – Jun 12

Peppers, eggplantStart indoors · Mar 13 – Mar 27

Peppers, eggplantTransplant · Jun 5 – Jun 19

BeansSow outdoors · May 29 – Jun 12

Sweet cornSow outdoors · May 29 – Jun 12

Cucumbers, squashSow outdoors · May 29 – Jun 12

Fall lettuce, spinachSow outdoors · Jul 26 – Aug 9

GarlicPlant cloves · Sep 6 – Oct 11

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 22) and first fall frost (Sep 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 58310 came on May 6 — 8 days later than the 1991–2020 average (Apr 28).

average
Apr 282026
May 6

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 Agate, ND

The soil mapped at the center of ZIP 58310 is Buse — loam, well drained.

TextureLoama good balance for most vegetables

pH7.9alkaline; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter2%moderate

Hydrologic groupBwater soaks in moderately

Farmland classNot prime farmlandUSDA classification

Map unit: Buse-Barnes-Langhei loams, 4 to 15 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 58310; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Agate, ND

Summer high78 °Faverage high, July

Winter low−8 °Faverage low, January

Hot days6days a year at 90 °F or more

Freezing nights206nights a year at 32 °F or less

Growing degree days1,620base 50 °F — the season’s usable heat

Longest day16 h 08 mindaylight on June 21

Shortest day8 h 17 mindaylight on December 21

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

Precipitation20.2 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: Rolette 3se, ND (12 mi away); precipitation: Rolette 3se, ND (12 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.

North Dakota planting zones →

Questions about 58310

What planting zone is ZIP code 58310?

ZIP code 58310 (Agate, ND) is in USDA hardiness zone 3b on the 2023 map: the coldest night of an average winter reaches −35 to −30 °F (−37.2 to −34.4 °C).

When is the last frost in Agate, ND?

The median last spring frost (32 °F) near 58310 is May 22; after June 3 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Rolette 3se station.

When is the first frost in Agate, ND?

The median first fall frost near 58310 is September 20, giving a median frost-free growing season of 120 days.

When should I plant tomatoes in 58310?

Start tomato seeds indoors around Mar 27 – Apr 10 and set transplants outside around May 29 – Jun 12, one to three weeks after the median last frost.

How much rain and snow does 58310 get?

About 20.2 inches of precipitation a year (NOAA 1991–2020 normals, Rolette 3se station).

How hot do summers get in Agate, ND?

The average high peaks at 78 °F in July, with about 6 days a year at 90 °F or more.

What kind of soil does 58310 have?

The USDA soil survey maps Buse at the center of ZIP 58310: loam, well drained, pH about 7.9 (alkaline).

Did spring come early in Agate, ND in 2026?

Spring leaf-out near 58310 came on May 6 in 2026, 8 days later than the 1991–2020 average (Apr 28), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Agate, ND?

Long-day onions: the longest day near 58310 is 16 h 08 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).