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

Planting zone for 86403 — Lake Havasu City, AZ

ZIP code 86403 (Lake Havasu City, Mohave County) is in USDA zone 10a: the coldest winter night averages 30 to 35 °F.

Where ZIP 86403 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.

Zone10a30 to 35 °F
Coldest night−1.1 to 1.7 °C
Last frostrare
First frostrare
2012 zone10a

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 10a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Lake Havasu City, AZ…

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

A 32 °F frost doesn't happen here in most winters. At the nearest station (NOAA station Lake Havasu City, AZ — 2 miles away, elevation 449 ft) the median growing season is 365 days. When frost does come, it is a midwinter night or two; cover tender plants when a freeze is forecast.

Frost data: NOAA NCEI U.S. Climate Normals 1991–2020.

When spring arrived in 2026

In 2026, spring leaf-out near 86403 came on Jan 18 — 5 days earlier than the 1991–2020 average (Jan 23).

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 10a in Arizona

506 plants native to the lower 48 states, recorded in Arizona, and rated by the USDA to survive 30 °F or colder — the bottom of zone 10a. Each links to its USDA PLANTS profile.

Trees 27

Shrubs 118

Wildflowers & perennials 199

Grasses 153

Vines 1

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 Lake Havasu City, AZ.

Soil in Lake Havasu City, AZ

The soil mapped at the center of ZIP 86403 is Coolidge — gravelly sandy loam, well drained.

TextureGravelly sandy loamdrains and warms fast; dries out and needs more feeding
pH7.9alkaline; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter0.75%low — add compost
Hydrologic groupAwater soaks in fast
Farmland classNot prime farmlandUSDA classification

Map unit: Coolidge-Denure complex, 1 to 7 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 86403; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Lake Havasu City, AZ

Summer high109 °Faverage high, July
Winter low42 °Faverage low, December
Hot days178days a year at 90 °F or more
Freezing nights1nights a year at 32 °F or less
Growing degree days8,902base 50 °F — the season’s usable heat
Longest day14 h 28 mindaylight on June 21
Shortest day9 h 51 mindaylight on December 21
Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully
Precipitation4.2 inper year, rain and melted snow

Average high and low, by month

30°40°50°60°70°80°90°100°110°120°32 °FJanuary: average high 65 °F, low 43 °F 65°43° JanFebruary: average high 70 °F, low 46 °F 70°46° FebMarch: average high 78 °F, low 51 °F 78°51° MarApril: average high 86 °F, low 58 °F 86°58° AprMay: average high 95 °F, low 67 °F 95°67° MayJune: average high 105 °F, low 76 °F 105°76° JunJuly: average high 109 °F, low 83 °F 109°83° JulAugust: average high 108 °F, low 82 °F 108°82° AugSeptember: average high 102 °F, low 75 °F 102°75° SepOctober: average high 89 °F, low 62 °F 89°62° OctNovember: average high 75 °F, low 50 °F 75°50° NovDecember: average high 64 °F, low 42 °F 64°42° Dec

Precipitation by month inches

0″1″January: 0.75 in precipitation 0.8 JanFebruary: 0.61 in precipitation 0.6 FebMarch: 0.48 in precipitation 0.5 MarApril: 0.16 in precipitation 0.2 AprMay: 0.03 in precipitation 0.0 MayJune: 0.01 in precipitation 0.0 JunJuly: 0.26 in precipitation 0.3 JulAugust: 0.38 in precipitation 0.4 AugSeptember: 0.36 in precipitation 0.4 SepOctober: 0.28 in precipitation 0.3 OctNovember: 0.30 in precipitation 0.3 NovDecember: 0.54 in precipitation 0.5 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Lake Havasu City, AZ (2 mi away); precipitation: Lake Havasu City, AZ (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

3 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

All 4 ZIP codes in Lake Havasu City → · Arizona planting zones →

Questions about 86403

What planting zone is ZIP code 86403?

ZIP code 86403 (Lake Havasu City, AZ) is in USDA hardiness zone 10a on the 2023 map: the coldest night of an average winter reaches 30 to 35 °F (−1.1 to 1.7 °C).

How much rain and snow does 86403 get?

About 4.2 inches of precipitation a year (NOAA 1991–2020 normals, Lake Havasu City station).

How hot do summers get in Lake Havasu City, AZ?

The average high peaks at 109 °F in July, with about 178 days a year at 90 °F or more.

What kind of soil does 86403 have?

The USDA soil survey maps Coolidge at the center of ZIP 86403: gravelly sandy loam, well drained, pH about 7.9 (alkaline).

Did spring come early in Lake Havasu City, AZ in 2026?

Spring leaf-out near 86403 came on Jan 18 in 2026, 5 days earlier than the 1991–2020 average (Jan 23), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Lake Havasu City, AZ?

Intermediate onions: the longest day near 86403 is 14 h 28 min, so day-neutral types bulb best; long-day varieties may not bulb fully.