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

Planting zone for 73561 — Oscar, OK

ZIP code 73561 (Oscar, Jefferson County) is in USDA zone 8a: the coldest winter night averages 10 to 15 °F. The median last spring frost is March 23 and the first fall frost November 7.

Where ZIP 73561 is

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.

Zone8a10 to 15 °F

Coldest night−12.2 to −9.4 °C

Last frostMar 23

First frostNov 7

2012 zone7b

Was 7b 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 8a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Oscar, 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 Oscar, OK

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMarch 23median — 50% chance of a later frost

Safe for tender plantsApril 13only 10% chance of frost after

First fall frostNovember 7median — 10% chance by Oct 24

Growing season226 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 10 and returns around November 17.

From the NOAA station Ringling 1n Mesonet, OK — 12 miles away, elevation 929 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 73561

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 9 – Feb 23

SpinachSow outdoors · Feb 9 – Mar 2

Broccoli, cabbageStart indoors · Jan 12 – Jan 26

Broccoli, cabbageTransplant · Mar 2 – Mar 16

Onion setsPlant outdoors · Feb 23 – Mar 9

PotatoesPlant outdoors · Mar 2 – Mar 16

LettuceSow outdoors · Feb 23 – Mar 9

Carrots, beetsSow outdoors · Mar 2 – Mar 16

TomatoesStart indoors · Jan 26 – Feb 9

TomatoesTransplant · Mar 30 – Apr 13

Peppers, eggplantStart indoors · Jan 12 – Jan 26

Peppers, eggplantTransplant · Apr 6 – Apr 20

BeansSow outdoors · Mar 30 – Apr 13

Sweet cornSow outdoors · Mar 30 – Apr 13

Cucumbers, squashSow outdoors · Mar 30 – Apr 13

Fall lettuce, spinachSow outdoors · Sep 12 – Sep 26

GarlicPlant cloves · Oct 24 – Nov 28

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 23) and first fall frost (Nov 7) 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 73561 came on Feb 9 — 3 days earlier than the 1991–2020 average (Feb 12).

average
Feb 122026
Feb 9

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 8a in Oklahoma

525 plants native to the lower 48 states, recorded in Oklahoma, and rated by the USDA to survive 10 °F or colder — the bottom of zone 8a. Each links to its USDA PLANTS profile.

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 Oscar, OK.

Soil in Oscar, OK

The soil mapped at the center of ZIP 73561 is Zaneis — loam, well drained.

TextureLoama good balance for most vegetables

pH6.5neutral; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter2%moderate

Hydrologic groupBwater soaks in moderately

Farmland classprime farmlandUSDA classification

Map unit: Zaneis-Pawhuska complex, 0 to 3 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 73561; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Oscar, OK

Summer high95 °Faverage high, July

Winter low30 °Faverage low, January

Hot days93days a year at 90 °F or more

Freezing nights62nights a year at 32 °F or less

Growing degree days5,689base 50 °F — the season’s usable heat

Longest day14 h 25 mindaylight on June 21

Shortest day9 h 53 mindaylight on December 21

Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully

Precipitation35 inper year, rain and melted snow

Snowfall2 inper year; 1 days with snow on the ground

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Ringling 1n Mesonet, OK (12 mi away); precipitation: Grady 2e, OK (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 8a.

Burneyville, OK · 19 mi

734388a

Healdton, OK · 19 mi

Oklahoma planting zones →

Questions about 73561

What planting zone is ZIP code 73561?

ZIP code 73561 (Oscar, OK) is in USDA hardiness zone 8a on the 2023 map: the coldest night of an average winter reaches 10 to 15 °F (−12.2 to −9.4 °C).

When is the last frost in Oscar, OK?

The median last spring frost (32 °F) near 73561 is March 23; after April 13 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Ringling 1n Mesonet station.

When is the first frost in Oscar, OK?

The median first fall frost near 73561 is November 7, giving a median frost-free growing season of 226 days.

When should I plant tomatoes in 73561?

Start tomato seeds indoors around Jan 26 – Feb 9 and set transplants outside around Mar 30 – Apr 13, one to three weeks after the median last frost.

How much rain and snow does 73561 get?

About 35 inches of precipitation a year and 2 inches of snowfall (NOAA 1991–2020 normals, Grady 2e station).

How hot do summers get in Oscar, OK?

The average high peaks at 95 °F in July, with about 93 days a year at 90 °F or more.

What kind of soil does 73561 have?

The USDA soil survey maps Zaneis at the center of ZIP 73561: loam, well drained, pH about 6.5 (neutral).

Did spring come early in Oscar, OK in 2026?

Spring leaf-out near 73561 came on Feb 9 in 2026, 3 days earlier than the 1991–2020 average (Feb 12), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Oscar, OK?

Intermediate onions: the longest day near 73561 is 14 h 25 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 73561 change?

Yes. The 2012 USDA map put 73561 in zone 7b; the 2023 map puts it in zone 8a. The newer map uses 1991–2020 data and more weather stations.