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

Planting zone for 64638 — Dawn, MO

ZIP code 64638 (Dawn, Livingston County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is April 15 and the first fall frost October 21.

Where ZIP 64638 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.

Zone6a−10 to −5 °F

Coldest night−23.3 to −20.6 °C

Last frostApr 15

First frostOct 21

2012 zone5b

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 Service

Loading the forecast for Dawn, MO…

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 Dawn, MO

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 15median — 50% chance of a later frost

Safe for tender plantsApril 30only 10% chance of frost after

First fall frostOctober 21median — 10% chance by Oct 7

Growing season187 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 5 and returns around November 1.

From the NOAA station Chillicothe 2s, MO — 12 miles away, elevation 781 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 64638

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 4 – Mar 18

SpinachSow outdoors · Mar 4 – Mar 25

Broccoli, cabbageStart indoors · Feb 4 – Feb 18

Broccoli, cabbageTransplant · Mar 25 – Apr 8

Onion setsPlant outdoors · Mar 18 – Apr 1

PotatoesPlant outdoors · Mar 25 – Apr 8

LettuceSow outdoors · Mar 18 – Apr 1

Carrots, beetsSow outdoors · Mar 25 – Apr 8

TomatoesStart indoors · Feb 18 – Mar 4

TomatoesTransplant · Apr 22 – May 6

Peppers, eggplantStart indoors · Feb 4 – Feb 18

Peppers, eggplantTransplant · Apr 29 – May 13

BeansSow outdoors · Apr 22 – May 6

Sweet cornSow outdoors · Apr 22 – May 6

Cucumbers, squashSow outdoors · Apr 22 – May 6

Fall lettuce, spinachSow outdoors · Aug 26 – Sep 9

GarlicPlant cloves · Oct 7 – Nov 11

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 15) and first fall frost (Oct 21) 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 64638 came on Mar 10 — 14 days earlier than the 1991–2020 average (Mar 24).

average
Mar 242026
Mar 10

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 6a in Missouri

516 plants native to the lower 48 states, recorded in Missouri, and rated by the USDA to survive −10 °F or colder — the bottom of zone 6a. 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 Dawn, MO.

Soil in Dawn, MO

The soil mapped at the center of ZIP 64638 is Dawn — loam, moderately well drained.

TextureLoama good balance for most vegetables

pH7.1neutral; most vegetables like 6.0–7.0

DrainageModerately well drainednatural drainage class

Organic matter2.75%moderate

Hydrologic groupC/Dslow when drained; wet otherwise

Farmland classNot prime farmlandUSDA classification

Map unit: Dawn loam, 5 to 9 percent slopes, eroded.

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 64638; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Dawn, MO

Summer high87 °Faverage high, July

Winter low16 °Faverage low, January

Hot days36days a year at 90 °F or more

Freezing nights123nights a year at 32 °F or less

Growing degree days3,699base 50 °F — the season’s usable heat

Longest day14 h 58 mindaylight on June 21

Shortest day9 h 22 mindaylight on December 21

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

Precipitation40.6 inper year, rain and melted snow

Snowfall14 inper year; 7 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: Chillicothe 2s, MO (12 mi away); precipitation: Coloma, MO (7 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

Mooresville, MO · 9 mi

646226a

Bogard, MO · 10 mi

646256a

Breckenridge, MO · 13 mi

646016a

Chillicothe, MO · 13 mi

Missouri planting zones →

Questions about 64638

What planting zone is ZIP code 64638?

ZIP code 64638 (Dawn, MO) 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 Dawn, MO?

The median last spring frost (32 °F) near 64638 is April 15; after April 30 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Chillicothe 2s station.

When is the first frost in Dawn, MO?

The median first fall frost near 64638 is October 21, giving a median frost-free growing season of 187 days.

When should I plant tomatoes in 64638?

Start tomato seeds indoors around Feb 18 – Mar 4 and set transplants outside around Apr 22 – May 6, one to three weeks after the median last frost.

How much rain and snow does 64638 get?

About 40.6 inches of precipitation a year and 14 inches of snowfall (NOAA 1991–2020 normals, Coloma station).

How hot do summers get in Dawn, MO?

The average high peaks at 87 °F in July, with about 36 days a year at 90 °F or more.

What kind of soil does 64638 have?

The USDA soil survey maps Dawn at the center of ZIP 64638: loam, moderately well drained, pH about 7.1 (neutral).

Did spring come early in Dawn, MO in 2026?

Spring leaf-out near 64638 came on Mar 10 in 2026, 14 days earlier than the 1991–2020 average (Mar 24), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Dawn, MO?

Intermediate onions: the longest day near 64638 is 14 h 58 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 64638 change?

Yes. The 2012 USDA map put 64638 in zone 5b; the 2023 map puts it in zone 6a. The newer map uses 1991–2020 data and more weather stations.