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

Planting zone for 65233 — Boonville, MO

ZIP code 65233 (Boonville, Cooper County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 12 and the first fall frost October 25.

Where ZIP 65233 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.

Zone6b−5 to 0 °F
Coldest night−20.6 to −17.8 °C
Last frostApr 12
First frostOct 25
2012 zone6a

Was 6a 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 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Boonville, 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 Boonville, 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 27only 10% chance of frost after
First fall frostOctober 25median — 10% chance by Oct 12
Growing season195 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 1 and returns around November 4.

From the NOAA station Boonville, MO — 4 miles away, elevation 751 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 65233

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 30 – Sep 13
GarlicPlant cloves · Oct 11 – Nov 15
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 12) and first fall frost (Oct 25) 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 65233 came on Mar 3 — 15 days earlier than the 1991–2020 average (Mar 18).

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 Boonville, MO

The soil mapped at the center of ZIP 65233 is Weller — silt loam, moderately well drained.

TextureSilt loama good balance for most vegetables
pH6.8neutral; most vegetables like 6.0–7.0
DrainageModerately well drainednatural drainage class
Organic matter2.9%moderate
Hydrologic groupDwater soaks in very slowly
Farmland classprime farmlandUSDA classification

Map unit: Weller silt loam, 2 to 5 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 65233; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Boonville, MO

Summer high88 °Faverage high, July
Winter low20 °Faverage low, January
Hot days39days a year at 90 °F or more
Freezing nights107nights a year at 32 °F or less
Growing degree days3,983base 50 °F — the season’s usable heat
Longest day14 h 54 mindaylight on June 21
Shortest day9 h 26 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation42 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 38 °F, low 20 °F 38°20° JanFebruary: average high 43 °F, low 23 °F 43°23° FebMarch: average high 55 °F, low 33 °F 55°33° MarApril: average high 65 °F, low 43 °F 65°43° AprMay: average high 75 °F, low 55 °F 75°55° MayJune: average high 84 °F, low 64 °F 84°64° JunJuly: average high 88 °F, low 68 °F 88°68° JulAugust: average high 87 °F, low 66 °F 87°66° AugSeptember: average high 80 °F, low 57 °F 80°57° SepOctober: average high 68 °F, low 46 °F 68°46° OctNovember: average high 54 °F, low 34 °F 54°34° NovDecember: average high 43 °F, low 25 °F 43°25° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 1.69 in precipitation 1.7 JanFebruary: 2.28 in precipitation 2.3 FebMarch: 3.12 in precipitation 3.1 MarApril: 4.23 in precipitation 4.2 AprMay: 4.80 in precipitation 4.8 MayJune: 4.89 in precipitation 4.9 JunJuly: 4.97 in precipitation 5.0 JulAugust: 3.55 in precipitation 3.5 AugSeptember: 3.87 in precipitation 3.9 SepOctober: 3.93 in precipitation 3.9 OctNovember: 2.88 in precipitation 2.9 NovDecember: 1.84 in precipitation 1.8 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Boonville, MO (4 mi away); precipitation: Boonville 3.7 Se, MO (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6b.

652746b
New Franklin, MO · 8 mi
650686b
Prairie Home, MO · 9 mi
652506b
Franklin, MO · 10 mi
652376b
Bunceton, MO · 11 mi
652876b
Wooldridge, MO · 11 mi
652796b
Rocheport, MO · 11 mi
652766b
Pilot Grove, MO · 13 mi
653226b
Blackwater, MO · 14 mi

Missouri planting zones →

Questions about 65233

What planting zone is ZIP code 65233?

ZIP code 65233 (Boonville, MO) is in USDA hardiness zone 6b on the 2023 map: the coldest night of an average winter reaches −5 to 0 °F (−20.6 to −17.8 °C).

When is the last frost in Boonville, MO?

The median last spring frost (32 °F) near 65233 is April 12; after April 27 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Boonville station.

When is the first frost in Boonville, MO?

The median first fall frost near 65233 is October 25, giving a median frost-free growing season of 195 days.

When should I plant tomatoes in 65233?

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 65233 get?

About 42 inches of precipitation a year (NOAA 1991–2020 normals, Boonville 3.7 Se station).

How hot do summers get in Boonville, MO?

The average high peaks at 88 °F in July, with about 39 days a year at 90 °F or more.

What kind of soil does 65233 have?

The USDA soil survey maps Weller at the center of ZIP 65233: silt loam, moderately well drained, pH about 6.8 (neutral).

Did spring come early in Boonville, MO in 2026?

Spring leaf-out near 65233 came on Mar 3 in 2026, 15 days earlier than the 1991–2020 average (Mar 18), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Boonville, MO?

Intermediate onions: the longest day near 65233 is 14 h 54 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 65233 change?

Yes. The 2012 USDA map put 65233 in zone 6a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.