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

Planting zone for 74643 — Lamont, OK

ZIP code 74643 (Lamont, Grant County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 18 and the first fall frost October 20.

Where ZIP 74643 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 18
First frostOct 20
2012 zone7a

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 7a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Lamont, OK…

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 Lamont, OK

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 18median — 50% chance of a later frost
Safe for tender plantsMay 2only 10% chance of frost after
First fall frostOctober 20median — 10% chance by Oct 4
Growing season183 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 9 and returns around October 28.

From the NOAA station Jefferson 3se, OK — 10 miles away, elevation 1,043 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 74643

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 7 – Mar 21
SpinachSow outdoors · Mar 7 – Mar 28
Broccoli, cabbageStart indoors · Feb 7 – Feb 21
Broccoli, cabbageTransplant · Mar 28 – Apr 11
Onion setsPlant outdoors · Mar 21 – Apr 4
PotatoesPlant outdoors · Mar 28 – Apr 11
LettuceSow outdoors · Mar 21 – Apr 4
Carrots, beetsSow outdoors · Mar 28 – Apr 11
TomatoesStart indoors · Feb 21 – Mar 7
TomatoesTransplant · Apr 25 – May 9
Peppers, eggplantStart indoors · Feb 7 – Feb 21
Peppers, eggplantTransplant · May 2 – May 16
BeansSow outdoors · Apr 25 – May 9
Sweet cornSow outdoors · Apr 25 – May 9
Cucumbers, squashSow outdoors · Apr 25 – May 9
Fall lettuce, spinachSow outdoors · Aug 25 – Sep 8
GarlicPlant cloves · Oct 6 – Nov 10
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 18) and first fall frost (Oct 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 74643 came on Feb 15 — 16 days earlier than the 1991–2020 average (Mar 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).

Soil in Lamont, OK

The soil mapped at the center of ZIP 74643 is Hawley — fine sandy loam, well drained.

TextureFine sandy loamdrains and warms fast; dries out and needs more feeding
pH6.7neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter0.5%low — add compost
Hydrologic groupBwater soaks in moderately
Farmland classprime farmlandUSDA classification

Map unit: Hawley fine sandy loam, 0 to 1 percent slopes, rarely flooded.

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 74643; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Lamont, OK

Summer high95 °Faverage high, July
Winter low20 °Faverage low, January
Hot days83days a year at 90 °F or more
Freezing nights110nights a year at 32 °F or less
Growing degree days4,528base 50 °F — the season’s usable heat
Longest day14 h 40 mindaylight on June 21
Shortest day9 h 39 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation36.2 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°110°32 °FJanuary: average high 48 °F, low 20 °F 48°20° JanFebruary: average high 52 °F, low 23 °F 52°23° FebMarch: average high 62 °F, low 32 °F 62°32° MarApril: average high 71 °F, low 41 °F 71°41° AprMay: average high 80 °F, low 53 °F 80°53° MayJune: average high 90 °F, low 63 °F 90°63° JunJuly: average high 95 °F, low 68 °F 95°68° JulAugust: average high 94 °F, low 66 °F 94°66° AugSeptember: average high 85 °F, low 57 °F 85°57° SepOctober: average high 74 °F, low 44 °F 74°44° OctNovember: average high 60 °F, low 32 °F 60°32° NovDecember: average high 49 °F, low 23 °F 49°23° Dec

Precipitation by month inches

0″1″2″3″4″5″6″January: 0.98 in precipitation 1.0 JanFebruary: 1.24 in precipitation 1.2 FebMarch: 2.88 in precipitation 2.9 MarApril: 3.52 in precipitation 3.5 AprMay: 5.08 in precipitation 5.1 MayJune: 4.98 in precipitation 5.0 JunJuly: 4.19 in precipitation 4.2 JulAugust: 3.74 in precipitation 3.7 AugSeptember: 2.87 in precipitation 2.9 SepOctober: 3.43 in precipitation 3.4 OctNovember: 2.00 in precipitation 2.0 NovDecember: 1.33 in precipitation 1.3 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Jefferson 3se, OK (10 mi away); precipitation: Hunter 6.0 Nne, OK (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 7a.

746407a
Hunter, OK · 7 mi
746367a
Deer Creek, OK · 12 mi
746537a
Tonkawa, OK · 13 mi
746307a
Billings, OK · 13 mi
746467a
Nardin, OK · 14 mi
737667a
Pond Creek, OK · 15 mi
737387a
Garber, OK · 15 mi
737597a
Medford, OK · 16 mi

Oklahoma planting zones →

Questions about 74643

What planting zone is ZIP code 74643?

ZIP code 74643 (Lamont, OK) 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 Lamont, OK?

The median last spring frost (32 °F) near 74643 is April 18; after May 2 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Jefferson 3se station.

When is the first frost in Lamont, OK?

The median first fall frost near 74643 is October 20, giving a median frost-free growing season of 183 days.

When should I plant tomatoes in 74643?

Start tomato seeds indoors around Feb 21 – Mar 7 and set transplants outside around Apr 25 – May 9, one to three weeks after the median last frost.

How much rain and snow does 74643 get?

About 36.2 inches of precipitation a year (NOAA 1991–2020 normals, Hunter 6.0 Nne station).

How hot do summers get in Lamont, OK?

The average high peaks at 95 °F in July, with about 83 days a year at 90 °F or more.

What kind of soil does 74643 have?

The USDA soil survey maps Hawley at the center of ZIP 74643: fine sandy loam, well drained, pH about 6.7 (neutral).

Did spring come early in Lamont, OK in 2026?

Spring leaf-out near 74643 came on Feb 15 in 2026, 16 days earlier than the 1991–2020 average (Mar 3), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Lamont, OK?

Intermediate onions: the longest day near 74643 is 14 h 40 min, so day-neutral types bulb best; long-day varieties may not bulb fully.