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

Planting zone for Carlsbad, CA

Carlsbad, CA is in USDA zones 10a to 10b across its 6 ZIP codes. The median last spring frost is January 23 and the first fall frost December 11.

Carlsbad on the zone map

Outlined: its 4 ZIP code areas · 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.

Zones10a–10b30 to 40 °F

ZIP codes6

Last frostJan 23

First frostDec 11

Growing season325 days

10a 4 ZIPs 10b 2 ZIPs

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Carlsbad, CA…

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 Carlsbad, CA

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostJanuary 23median — 50% chance of a later frost

Safe for tender plantsFebruary 22only 10% chance of frost after

First fall frostDecember 11median — 10% chance by Nov 21

Growing season325 daysfrost-free, median

A hard freeze (28 °F) usually ends around December 31 and returns around December 23.

From the NOAA station Oceanside Municipal Airport, CA, elevation 30 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 Carlsbad

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Dec 12 – Dec 26

SpinachSow outdoors · Dec 12 – Jan 2

Broccoli, cabbageStart indoors · Nov 14 – Nov 28

Broccoli, cabbageTransplant · Jan 2 – Jan 16

Onion setsPlant outdoors · Dec 26 – Jan 9

PotatoesPlant outdoors · Jan 2 – Jan 16

LettuceSow outdoors · Dec 26 – Jan 9

Carrots, beetsSow outdoors · Jan 2 – Jan 16

TomatoesStart indoors · Nov 28 – Dec 12

TomatoesTransplant · Jan 30 – Feb 13

Peppers, eggplantStart indoors · Nov 14 – Nov 28

Peppers, eggplantTransplant · Feb 6 – Feb 20

BeansSow outdoors · Jan 30 – Feb 13

Sweet cornSow outdoors · Jan 30 – Feb 13

Cucumbers, squashSow outdoors · Jan 30 – Feb 13

Fall lettuce, spinachSow outdoors · Oct 16 – Oct 30

GarlicPlant cloves · Nov 27 – Jan 1

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Jan 23) and first fall frost (Dec 11) 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 92008 came on Jan 18 — 6 days earlier than the 1991–2020 average (Jan 24).

average
Jan 242026
Jan 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 Carlsbad, CA

The soil mapped at the center of ZIP 92008 is Las Flores — loamy fine sand, moderately well drained.

TextureLoamy fine sanddrains and warms fast; dries out and needs more feeding

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

DrainageModerately well drainednatural drainage class

Organic matter0.75%low — add compost

Hydrologic groupDwater soaks in very slowly

Farmland classNot prime farmlandUSDA classification

Map unit: Las Flores loamy fine sand, 15 to 30 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 92008; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Carlsbad, CA

Summer high76 °Faverage high, August

Winter low47 °Faverage low, December

Hot days3days a year at 90 °F or more

Freezing nights0nights a year at 32 °F or less

Growing degree days4,583base 50 °F — the season’s usable heat

Longest day14 h 21 mindaylight on June 21

Shortest day9 h 57 mindaylight on December 21

Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully

Precipitation13.5 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Carlsbad Palomar Airport, CA (2 mi away); precipitation: Carlsbad 1.3ene, CA (2 mi away). Daylight is calculated from latitude.

ZIP codes in Carlsbad

California planting zones →

Questions about Carlsbad

What planting zone is Carlsbad, CA?

Carlsbad, CA is in USDA hardiness zones 10a to 10b on the 2023 map (10a: 30 to 35 °F; 10b: 35 to 40 °F).

When is the last frost in Carlsbad, CA?

The median last spring frost is January 23 and the median first fall frost is December 11 (NOAA 1991–2020 normals, Oceanside Municipal Airport station).

When can I plant a garden in Carlsbad, CA?

Cool-season crops like peas and spinach go in around Dec 12 – Jan 2; tomatoes, peppers, beans and squash after about Jan 30, once frost risk has passed.

What kind of onions grow in Carlsbad, CA?

Intermediate onions: the longest day is 14 h 21 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

How much rain and snow does Carlsbad, CA get?

About 13.5 inches of precipitation a year (NOAA 1991–2020 normals).