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

Planting zone for 65039 — Hartsburg, MO

ZIP code 65039 (Hartsburg, Boone County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 7 and the first fall frost October 29.

Where ZIP 65039 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 7
First frostOct 29
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 Hartsburg, 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 Hartsburg, MO

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 7median — 50% chance of a later frost
Safe for tender plantsApril 21only 10% chance of frost after
First fall frostOctober 29median — 10% chance by Oct 16
Growing season205 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 28 and returns around November 6.

From the NOAA station Columbia Regional Airport, MO — 9 miles away, elevation 892 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 65039

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Feb 24 – Mar 10
SpinachSow outdoors · Feb 24 – Mar 17
Broccoli, cabbageStart indoors · Jan 27 – Feb 10
Broccoli, cabbageTransplant · Mar 17 – Mar 31
Onion setsPlant outdoors · Mar 10 – Mar 24
PotatoesPlant outdoors · Mar 17 – Mar 31
LettuceSow outdoors · Mar 10 – Mar 24
Carrots, beetsSow outdoors · Mar 17 – Mar 31
TomatoesStart indoors · Feb 10 – Feb 24
TomatoesTransplant · Apr 14 – Apr 28
Peppers, eggplantStart indoors · Jan 27 – Feb 10
Peppers, eggplantTransplant · Apr 21 – May 5
BeansSow outdoors · Apr 14 – Apr 28
Sweet cornSow outdoors · Apr 14 – Apr 28
Cucumbers, squashSow outdoors · Apr 14 – Apr 28
Fall lettuce, spinachSow outdoors · Sep 3 – Sep 17
GarlicPlant cloves · Oct 15 – Nov 19
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 7) and first fall frost (Oct 29) 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 65039 came on Mar 5 — 11 days earlier than the 1991–2020 average (Mar 16).

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 6b in Missouri

525 plants native to the lower 48 states, recorded in Missouri, and rated by the USDA to survive −5 °F or colder — the bottom of zone 6b. Each links to its USDA PLANTS profile.

Trees 70

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 83

alternateleaf dogwood25 ft · blooms mid spring · low shade tolerance · to −47 °FAmerican beautyberry6 ft · blooms early summer · medium shade tolerance · to −8 °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 °F

Wildflowers & perennials 192

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 157

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 12

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 °Fgraybark grape50 ft · blooms late spring · medium shade tolerance · to −8 °Fheartleaf peppervine2 ft · blooms late spring · low shade tolerance · to −8 °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 Hartsburg, MO.

Soil in Hartsburg, MO

The soil mapped at the center of ZIP 65039 is Menfro — silt loam, well drained.

TextureSilt loama good balance for most vegetables
pH5.5moderately acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter3.5%moderate
Hydrologic groupBwater soaks in moderately
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Menfro silt loam, 9 to 14 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 65039; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Hartsburg, MO

Summer high89 °Faverage high, July
Winter low23 °Faverage low, January
Hot days35days a year at 90 °F or more
Freezing nights101nights a year at 32 °F or less
Growing degree days4,226base 50 °F — the season’s usable heat
Longest day14 h 53 mindaylight on June 21
Shortest day9 h 27 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation43.9 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 40 °F, low 23 °F 40°23° JanFebruary: average high 45 °F, low 26 °F 45°26° FebMarch: average high 56 °F, low 36 °F 56°36° MarApril: average high 67 °F, low 46 °F 67°46° AprMay: average high 76 °F, low 56 °F 76°56° MayJune: average high 85 °F, low 65 °F 85°65° JunJuly: average high 89 °F, low 69 °F 89°69° JulAugust: average high 88 °F, low 67 °F 88°67° AugSeptember: average high 80 °F, low 58 °F 80°58° SepOctober: average high 68 °F, low 47 °F 68°47° OctNovember: average high 55 °F, low 36 °F 55°36° NovDecember: average high 44 °F, low 27 °F 44°27° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 2.29 in precipitation 2.3 JanFebruary: 2.31 in precipitation 2.3 FebMarch: 3.26 in precipitation 3.3 MarApril: 5.00 in precipitation 5.0 AprMay: 4.90 in precipitation 4.9 MayJune: 4.56 in precipitation 4.6 JunJuly: 4.63 in precipitation 4.6 JulAugust: 3.96 in precipitation 4.0 AugSeptember: 4.10 in precipitation 4.1 SepOctober: 3.76 in precipitation 3.8 OctNovember: 2.95 in precipitation 3.0 NovDecember: 2.17 in precipitation 2.2 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Columbia Regional Airport, MO (9 mi away); precipitation: Ashland 0.7 Wnw, MO (5 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6b.

650106b
Ashland, MO · 6 mi
650236b
Centertown, MO · 7 mi
651096b
Jefferson City, MO · 10 mi
650466b
Jamestown, MO · 11 mi
650636b
New Bloomfield, MO · 11 mi
651026b
Jefferson City, MO · 11 mi
651036b
Jefferson City, MO · 11 mi
651046b
Jefferson City, MO · 11 mi

Missouri planting zones →

Questions about 65039

What planting zone is ZIP code 65039?

ZIP code 65039 (Hartsburg, 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 Hartsburg, MO?

The median last spring frost (32 °F) near 65039 is April 7; after April 21 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Columbia Regional Airport station.

When is the first frost in Hartsburg, MO?

The median first fall frost near 65039 is October 29, giving a median frost-free growing season of 205 days.

When should I plant tomatoes in 65039?

Start tomato seeds indoors around Feb 10 – Feb 24 and set transplants outside around Apr 14 – Apr 28, one to three weeks after the median last frost.

How much rain and snow does 65039 get?

About 43.9 inches of precipitation a year (NOAA 1991–2020 normals, Ashland 0.7 Wnw station).

How hot do summers get in Hartsburg, MO?

The average high peaks at 89 °F in July, with about 35 days a year at 90 °F or more.

What kind of soil does 65039 have?

The USDA soil survey maps Menfro at the center of ZIP 65039: silt loam, well drained, pH about 5.5 (moderately acidic).

Did spring come early in Hartsburg, MO in 2026?

Spring leaf-out near 65039 came on Mar 5 in 2026, 11 days earlier than the 1991–2020 average (Mar 16), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Hartsburg, MO?

Intermediate onions: the longest day near 65039 is 14 h 53 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 65039 change?

Yes. The 2012 USDA map put 65039 in zone 6a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.