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

Planting zone for 63456 — Monroe City, MO

ZIP code 63456 (Monroe City, Monroe County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is April 12 and the first fall frost October 22.

Where ZIP 63456 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 12
First frostOct 22
2012 zone6a

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 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Monroe City, 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 Monroe City, MO

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 12median — 50% chance of a later frost
Safe for tender plantsApril 28only 10% chance of frost after
First fall frostOctober 22median — 10% chance by Oct 7
Growing season190 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 2 and returns around November 1.

From the NOAA station Monroe City, MO — within 1 mile, elevation 742 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 63456

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 1 – Mar 15
SpinachSow outdoors · Mar 1 – Mar 22
Broccoli, cabbageStart indoors · Feb 1 – Feb 15
Broccoli, cabbageTransplant · Mar 22 – Apr 5
Onion setsPlant outdoors · Mar 15 – Mar 29
PotatoesPlant outdoors · Mar 22 – Apr 5
LettuceSow outdoors · Mar 15 – Mar 29
Carrots, beetsSow outdoors · Mar 22 – Apr 5
TomatoesStart indoors · Feb 15 – Mar 1
TomatoesTransplant · Apr 19 – May 3
Peppers, eggplantStart indoors · Feb 1 – Feb 15
Peppers, eggplantTransplant · Apr 26 – May 10
BeansSow outdoors · Apr 19 – May 3
Sweet cornSow outdoors · Apr 19 – May 3
Cucumbers, squashSow outdoors · Apr 19 – May 3
Fall lettuce, spinachSow outdoors · Aug 27 – Sep 10
GarlicPlant cloves · Oct 8 – Nov 12
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 12) and first fall frost (Oct 22) 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 63456 came on Mar 10 — 12 days earlier than the 1991–2020 average (Mar 22).

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.

Trees 68

American basswood100 ft · blooms late spring · low shade tolerance · to −46 °FAmerican beech80 ft · blooms mid spring · low shade tolerance · to −44 °FAmerican chestnut115 ft · blooms early summer · high shade tolerance · to −33 °FAmerican elm120 ft · blooms early spring · medium shade tolerance · to −46 °FAmerican sycamore100 ft · blooms spring · medium shade tolerance · to −34 °Fbald cypress130 ft · blooms mid spring · medium shade tolerance · to −18 °F

Shrubs 82

alternateleaf dogwood25 ft · blooms mid spring · low shade tolerance · to −47 °FAmerican black currant3 ft · blooms early spring · to −46 °FAmerican hazelnut10 ft · blooms spring · medium shade tolerance · to −33 °FAmerican holly40 ft · blooms mid spring · low shade tolerance · to −20 °FAmerican hornbeam30 ft · blooms mid spring · low shade tolerance · to −34 °FAmerican plum24 ft · blooms mid spring · high shade tolerance · to −38 °F

Wildflowers & perennials 190

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °FAmerican bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °FAmerican licorice4 ft · blooms late spring · medium shade tolerance · to −38 °FAmerican lotus3 ft · blooms mid summer · high shade tolerance · to −36 °FAmerican pokeweed7 ft · blooms mid summer · low shade tolerance · to −33 °F

Grasses 155

alkali sacaton3 ft · blooms mid summer · high shade tolerance · to −38 °FAmerican cupscale3 ft · blooms early summer · high shade tolerance · to −18 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °FBicknell's sedge3 ft · blooms late spring · low shade tolerance · to −38 °Fbig bluestem6 ft · blooms summer · high shade tolerance · to −46 °Fblister sedge3 ft · blooms late spring · medium shade tolerance · to −38 °F

Vines 10

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °Fcatbird grape30 ft · blooms late spring · medium shade tolerance · to −13 °Fdevil's darning needles15 ft · blooms mid summer · medium shade tolerance · to −38 °Ffrost grape83 ft · blooms late spring · medium shade tolerance · to −23 °Fmuscadine30 ft · blooms late spring · medium shade tolerance · to −18 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °F

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 Monroe City, MO.

Soil in Monroe City, MO

The soil mapped at the center of ZIP 63456 is Mexico — silt loam, poorly drained.

TextureSilt loama good balance for most vegetables
pH6.5neutral; most vegetables like 6.0–7.0
DrainagePoorly drainedconsider raised beds
Organic matter1.87%low — add compost
Hydrologic groupDwater soaks in very slowly
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Mexico silt loam, 1 to 4 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 63456; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Monroe City, MO

Summer high86 °Faverage high, July
Winter low18 °Faverage low, January
Hot days30days a year at 90 °F or more
Freezing nights121nights a year at 32 °F or less
Growing degree days3,669base 50 °F — the season’s usable heat
Longest day14 h 59 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
Precipitation41.7 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 36 °F, low 18 °F 36°18° JanFebruary: average high 40 °F, low 21 °F 40°21° FebMarch: average high 52 °F, low 32 °F 52°32° MarApril: average high 64 °F, low 42 °F 64°42° AprMay: average high 73 °F, low 54 °F 73°54° MayJune: average high 83 °F, low 63 °F 83°63° JunJuly: average high 86 °F, low 66 °F 86°66° JulAugust: average high 85 °F, low 64 °F 85°64° AugSeptember: average high 79 °F, low 55 °F 79°55° SepOctober: average high 67 °F, low 44 °F 67°44° OctNovember: average high 53 °F, low 32 °F 53°32° NovDecember: average high 41 °F, low 23 °F 41°23° Dec

Precipitation by month inches

0″1″2″3″4″5″6″January: 1.82 in precipitation 1.8 JanFebruary: 2.01 in precipitation 2.0 FebMarch: 2.92 in precipitation 2.9 MarApril: 4.28 in precipitation 4.3 AprMay: 5.04 in precipitation 5.0 MayJune: 5.36 in precipitation 5.4 JunJuly: 4.58 in precipitation 4.6 JulAugust: 3.77 in precipitation 3.8 AugSeptember: 3.92 in precipitation 3.9 SepOctober: 3.30 in precipitation 3.3 OctNovember: 2.65 in precipitation 2.6 NovDecember: 2.04 in precipitation 2.0 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Monroe City, MO (within 1 mile); precipitation: Monroe City, MO (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6a.

634436a
Hunnewell, MO · 8 mi
652836a
Stoutsville, MO · 11 mi
634396a
Emden, MO · 13 mi
634616a
Palmyra, MO · 14 mi
634636a
Philadelphia, MO · 14 mi
634016a
Hannibal, MO · 14 mi
634366a
Center, MO · 15 mi
634626a
Perry, MO · 16 mi

Missouri planting zones →

Questions about 63456

What planting zone is ZIP code 63456?

ZIP code 63456 (Monroe City, 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 Monroe City, MO?

The median last spring frost (32 °F) near 63456 is April 12; after April 28 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Monroe City station.

When is the first frost in Monroe City, MO?

The median first fall frost near 63456 is October 22, giving a median frost-free growing season of 190 days.

When should I plant tomatoes in 63456?

Start tomato seeds indoors around Feb 15 – Mar 1 and set transplants outside around Apr 19 – May 3, one to three weeks after the median last frost.

How much rain and snow does 63456 get?

About 41.7 inches of precipitation a year (NOAA 1991–2020 normals, Monroe City station).

How hot do summers get in Monroe City, MO?

The average high peaks at 86 °F in July, with about 30 days a year at 90 °F or more.

What kind of soil does 63456 have?

The USDA soil survey maps Mexico at the center of ZIP 63456: silt loam, poorly drained, pH about 6.5 (neutral).

Did spring come early in Monroe City, MO in 2026?

Spring leaf-out near 63456 came on Mar 10 in 2026, 12 days earlier than the 1991–2020 average (Mar 22), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Monroe City, MO?

Intermediate onions: the longest day near 63456 is 14 h 59 min, so day-neutral types bulb best; long-day varieties may not bulb fully.