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

Planting zone for 66045 — Lawrence, KS

ZIP code 66045 (Lawrence, Douglas 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 28.

Where ZIP 66045 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 28

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 Lawrence, KS…

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 Lawrence, KS

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 24only 10% chance of frost after

First fall frostOctober 28median — 10% chance by Oct 14

Growing season199 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 3 and returns around November 4.

From the NOAA station Lawrence, KS — within 1 mile, elevation 1,050 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 66045

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 · Sep 2 – Sep 16

GarlicPlant cloves · Oct 14 – Nov 18

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 12) and first fall frost (Oct 28) 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 66045 came on Feb 28 — 18 days earlier than the 1991–2020 average (Mar 18).

average
Mar 182026
Feb 28

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 Kansas

431 plants native to the lower 48 states, recorded in Kansas, and rated by the USDA to survive −5 °F or colder — the bottom of zone 6b. 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 Lawrence, KS.

Soil in Lawrence, KS

The soil mapped at the center of ZIP 66045 is Oska — silty clay loam, well drained.

TextureSilty clay loamholds water and nutrients; slow to drain and warm up

pH6.1slightly acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter3%moderate

Hydrologic groupDwater soaks in very slowly

Farmland classFarmland of statewide importanceUSDA classification

Map unit: Oska silty clay loam, 3 to 6 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 66045; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Lawrence, KS

Summer high89 °Faverage high, July

Winter low19 °Faverage low, January

Hot days42days a year at 90 °F or more

Freezing nights104nights a year at 32 °F or less

Growing degree days4,113base 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

Precipitation39.4 inper year, rain and melted snow

Snowfall10 inper year; 13 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: Lawrence, KS (within 1 mile); precipitation: Lawrence, KS (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6b.

Lecompton, KS · 10 mi

Baldwin City, KS · 12 mi

All 5 ZIP codes in Lawrence → · Kansas planting zones →

Questions about 66045

What planting zone is ZIP code 66045?

ZIP code 66045 (Lawrence, KS) 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 Lawrence, KS?

The median last spring frost (32 °F) near 66045 is April 12; after April 24 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Lawrence station.

When is the first frost in Lawrence, KS?

The median first fall frost near 66045 is October 28, giving a median frost-free growing season of 199 days.

When should I plant tomatoes in 66045?

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 66045 get?

About 39.4 inches of precipitation a year and 10 inches of snowfall (NOAA 1991–2020 normals, Lawrence station).

How hot do summers get in Lawrence, KS?

The average high peaks at 89 °F in July, with about 42 days a year at 90 °F or more.

What kind of soil does 66045 have?

The USDA soil survey maps Oska at the center of ZIP 66045: silty clay loam, well drained, pH about 6.1 (slightly acidic).

Did spring come early in Lawrence, KS in 2026?

Spring leaf-out near 66045 came on Feb 28 in 2026, 18 days earlier than the 1991–2020 average (Mar 18), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Lawrence, KS?

Intermediate onions: the longest day near 66045 is 14 h 54 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 66045 change?

Yes. The 2012 USDA map put 66045 in zone 6a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.