US Grow Zones

Perris, California: planting zone & frost dates

Last updated · Sources: PRISM/OSU 2023 ZIP zone listings; NOAA NCEI 1991–2020 Climate Normals (station USC00042805); U.S. Census Bureau — see methodology

Perris is in USDA plant hardiness zone 9b, where the average coldest winter night reaches 25 to 30°F (-3.9 to -1.1°C). The typical last spring frost is around Feb 10 and the first fall frost around Dec 10.

Hardiness zone9B25 to 30°F
Last spring frostFeb 1030% chance of frost after
First fall frostDec 1030% chance of frost before
Growing season329 daysmedian frost-free days

Frost dates

ProbabilityLast spring frost (32°F)First fall frost (32°F)
Safer (10% risk)Feb 27Dec 1
Typical planning date (30% risk)Feb 10Dec 10
Median (50%)Jan 28Dec 18

How to read this: after the spring "10% risk" date, a 32°F frost happens in only about 1 year in 10. In fall, the "10% risk" date is the early end — a frost before it happens about 1 year in 10.

Frost data comes from NOAA station ELSINORE, CA (USC00042805), 10.1 mi (16.2 km) from the city center and 164 ft lower than the city center (-50 m). Record used for the 1991–2020 normals: 19 years.

Frost probability in spring and fall, Perris, CAChance of a 32°F frost in Perris, CA, NOAA 1991–2020. Spring: the chance of another frost falls from 90% on Dec 24 to 10% on Feb 27. Fall: the chance that the first frost has arrived rises from 10% on Dec 1 to 90% on Jan 24.0%50%100%Spring: later frostDec 15Jan 15Feb 1530%: Feb 10Fall: frost arrivedDec 1Jan 1Feb 130%: Dec 1032°F frost28°F hard freezeplanning date
Shaded areas show the chance of a 32°F frost: falling through spring, rising through fall. The dashed line is the 28°F hard-freeze curve. Data: NOAA 1991–2020 Normals, station USC00042805.
Frost-free growing season in Perris, CA1 in 10 risk: Feb 27 to Dec 1 (277 days); 3 in 10 risk: Feb 10 to Dec 10 (303 days); Median (50%): Jan 28 to Dec 18 (324 days); No 28°F freeze: Jan 1 to Dec 27 (360 days). In 9 of 10 years the 32°F-free season is at least 287 days.Frost-free days, spring to fallJFMAMJJASOND1 in 10 risk277 days3 in 10 risk303 daysMedian (50%)324 daysNo 28°F freeze360 days
Frost-free window at three risk levels, plus the window between 28°F hard freezes. Read about what the probabilities mean.

Why your yard may differ from the station: microclimates.

Hardiness zone across Perris

All 2 ZIP codes covering Perris are in zone 9b.

ZIP codes in Perris and their zones
ZIPZoneShare of city land
925719b49.5%
925709b48.5%

Vegetable planting calendar for Perris

Dates are counted from the 30%-risk frost dates above (last frost Feb 10, first frost Dec 10). Shift a week later in cold spots or low-lying ground.

CropStart indoorsTransplant / plant outDirect sowFall crop sow/plant
TomatoDec 16 – Dec 30Feb 17 – Mar 3——
PepperDec 2 – Dec 16Feb 24 – Mar 10——
Lettuce
Mild winters: fall and winter plantings are usually more reliable than spring.
Dec 30 – Jan 13Jan 27 – Feb 17Jan 13 – Feb 24Oct 1 – Oct 29
Green Beans——Feb 17 – Mar 24Sep 17 – Oct 1
Sweet Corn——Feb 17 – Mar 17—
Zucchini & Summer SquashJan 13 – Jan 20Feb 17 – Mar 3Feb 17 – Mar 10Sep 17 – Oct 1
CucumberJan 13 – Jan 20Feb 24 – Mar 3Feb 17 – Mar 10Sep 17 – Oct 1
Carrot
Mild winters: fall and winter plantings are usually more reliable than spring.
——Jan 20 – Feb 24Sep 17 – Oct 1
Onion
Mild winters: fall and winter plantings are usually more reliable than spring.
Nov 18 – Dec 2Jan 13 – Jan 27——
Potato
Mild winters: fall and winter plantings are usually more reliable than spring.
—Jan 13 – Feb 3——
BasilDec 30 – Jan 13Feb 24 – Mar 10Feb 24 – Mar 17—
Spinach
Mild winters: fall and winter plantings are usually more reliable than spring.
——Dec 30 – Jan 27Oct 15 – Nov 12
Kale
Mild winters: fall and winter plantings are usually more reliable than spring.
Dec 16 – Dec 30Jan 13 – Feb 3Jan 13 – Feb 3Oct 1 – Oct 29
Broccoli
Mild winters: fall and winter plantings are usually more reliable than spring.
Dec 16 – Dec 30Jan 27 – Feb 17—Sep 17 – Oct 1
Peas
Mild winters: fall and winter plantings are usually more reliable than spring.
——Dec 30 – Jan 20Oct 1 – Oct 15
EggplantDec 2 – Dec 16Feb 24 – Mar 10——
Cabbage
Mild winters: fall and winter plantings are usually more reliable than spring.
Dec 16 – Dec 30Jan 13 – Jan 27—Sep 17 – Oct 1
Radish
Mild winters: fall and winter plantings are usually more reliable than spring.
——Jan 6 – Feb 24Oct 29 – Nov 26
Strawberry—Jan 13 – Feb 3——
Beets
Mild winters: fall and winter plantings are usually more reliable than spring.
——Jan 20 – Mar 3Oct 1 – Oct 15

Nearby cities in California

More: all California cities · other zone 9b cities: Houston, TX, Phoenix, AZ, Jacksonville, FL, San Jose, CA, Fresno, CA, Sacramento, CA, Mesa, AZ, Bakersfield, CA

Perris gardening questions

When is the last frost in Perris, CA?

Plan around Feb 10. At NOAA's Elsinore, CA station, 10.1 mi from the city center, there is a 30% chance of a 32°F frost after that date. Half of springs have their last frost by Jan 28, and after Feb 27 the risk drops to about 1 in 10. A hard freeze (28°F) usually ends earlier, around Jan 1. Springs here are erratic: 65 days separate the 90% and 10% dates, versus a median of 36 days for cities on this site, so watch the forecast rather than the calendar.

When should I plant tomatoes in Perris, CA?

Start seeds indoors Dec 16 – Dec 30 and set transplants outside Feb 17 – Mar 3, once nights stay above 50°F and the soil is near 60°F. With about 303 frost-free days, frost is not the main limit — fruit set drops when nights stay above about 75°F, so early plantings tend to do best. More: tomato planting dates by zone.

How long is the growing season in Perris?

About 329 days without a 32°F frost in a typical (median) year. In 9 years out of 10 the season lasts at least 287 days, and in 1 year in 10 it runs 361 days or more. In fall there is a 10% chance of frost by Dec 1 and a 30% chance by Dec 10. That ranks 59th longest of 84 California cities on this site.

When should I plant a fall garden in Perris?

Count back from the first fall frost (Dec 10): transplant broccoli Sep 17 – Oct 1; sow kale Oct 1 – Oct 29; sow lettuce Oct 1 – Oct 29; sow radishes Oct 29 – Nov 26. Hardy crops keep growing through light frosts; the median 28°F hard freeze here is Dec 27. How the math works: succession and fall planting.

Did Perris's hardiness zone change on the 2023 map?

No. Going by the zone that covers most of the city's land, Perris is zone 9b on both the 2012 and the 2023 USDA maps (PRISM/OSU ZIP listings). About 42% of U.S. ZIP codes kept their half-zone in 2023. Why the 2023 map is warmer.

How does Perris compare with Moreno Valley, CA?

Both are in zone 9b. The typical last spring frost in Perris (Feb 10) comes about the same time as in Moreno Valley, CA (Feb 10), 9 miles away, and the first fall frost is Dec 10 versus Dec 11. Perris sits about 187 ft lower, which explains part of the gap. The two cities use different NOAA stations.