US Grow Zones

Tracy, California: planting zone & frost dates

Last updated · Sources: PRISM/OSU 2023 ZIP zone listings; NOAA NCEI 1991–2020 Climate Normals (station USC00048999); U.S. Census Bureau — see methodology

Tracy 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 Mar 9 and the first fall frost around Nov 20.

Hardiness zone9B25 to 30°F
Last spring frostMar 930% chance of frost after
First fall frostNov 2030% chance of frost before
Growing season272 daysmedian frost-free days

Frost dates

ProbabilityLast spring frost (32°F)First fall frost (32°F)
Safer (10% risk)Apr 6Nov 8
Typical planning date (30% risk)Mar 9Nov 20
Median (50%)Feb 25Nov 26

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 TRACY CARBONA, CA (USC00048999), 6.6 mi (10.6 km) from the city center and 72 ft higher than the city center (+22 m). Record used for the 1991–2020 normals: 23 years.

Frost probability in spring and fall, Tracy, CAChance of a 32°F frost in Tracy, CA, NOAA 1991–2020. Spring: the chance of another frost falls from 90% on Jan 24 to 10% on Apr 6. Fall: the chance that the first frost has arrived rises from 10% on Nov 8 to 90% on Dec 12.0%50%100%Spring: later frostJan 1Feb 1Mar 1Apr 130%: Mar 9Fall: frost arrivedNov 1Dec 1Jan 130%: Nov 2032°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 USC00048999.
Frost-free growing season in Tracy, CA1 in 10 risk: Apr 6 to Nov 8 (216 days); 3 in 10 risk: Mar 9 to Nov 20 (256 days); Median (50%): Feb 25 to Nov 26 (274 days); No 28°F freeze: Jan 18 to Dec 11 (327 days). In 9 of 10 years the 32°F-free season is at least 228 days.Frost-free days, spring to fallJFMAMJJASOND1 in 10 risk216 days3 in 10 risk256 daysMedian (50%)274 daysNo 28°F freeze327 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 Tracy

All 3 ZIP codes covering Tracy are in zone 9b.

ZIP codes in Tracy and their zones
ZIPZoneShare of city land
953779b52.4%
953769b27.7%
953049b19.9%

Vegetable planting calendar for Tracy

Dates are counted from the 30%-risk frost dates above (last frost Mar 9, first frost Nov 20). Shift a week later in cold spots or low-lying ground.

CropStart indoorsTransplant / plant outDirect sowFall crop sow/plant
TomatoJan 12 – Jan 26Mar 16 – Mar 30——
PepperDec 29 – Jan 12Mar 23 – Apr 6——
LettuceJan 26 – Feb 9Feb 23 – Mar 16Feb 9 – Mar 23Sep 11 – Oct 9
Green Beans——Mar 16 – Apr 20Aug 28 – Sep 11
Sweet Corn——Mar 16 – Apr 13—
Zucchini & Summer SquashFeb 9 – Feb 16Mar 16 – Mar 30Mar 16 – Apr 6Aug 28 – Sep 11
CucumberFeb 9 – Feb 16Mar 23 – Mar 30Mar 16 – Apr 6Aug 28 – Sep 11
Carrot——Feb 16 – Mar 23Aug 28 – Sep 11
OnionDec 15 – Dec 29Feb 9 – Feb 23——
Potato—Feb 9 – Mar 2——
BasilJan 26 – Feb 9Mar 23 – Apr 6Mar 23 – Apr 13—
Spinach——Jan 26 – Feb 23Sep 25 – Oct 23
KaleJan 12 – Jan 26Feb 9 – Mar 2Feb 9 – Mar 2Sep 11 – Oct 9
BroccoliJan 12 – Jan 26Feb 23 – Mar 16—Aug 28 – Sep 11
Peas——Jan 26 – Feb 16Sep 11 – Sep 25
EggplantDec 29 – Jan 12Mar 23 – Apr 6——
CabbageJan 12 – Jan 26Feb 9 – Feb 23—Aug 28 – Sep 11
Radish——Feb 2 – Mar 23Oct 9 – Nov 6
Strawberry—Feb 9 – Mar 2——
Beets——Feb 16 – Mar 30Sep 11 – Sep 25

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

Tracy gardening questions

When is the last frost in Tracy, CA?

Plan around Mar 9. At NOAA's Tracy Carbona, CA station, 6.6 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 Feb 25, and after Apr 6 the risk drops to about 1 in 10. A hard freeze (28°F) usually ends earlier, around Jan 18. Springs here are erratic: 72 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 Tracy, CA?

Start seeds indoors Jan 12 – Jan 26 and set transplants outside Mar 16 – Mar 30, once nights stay above 50°F and the soil is near 60°F. That leaves 256 days between the 30% frost dates, enough for most varieties including 80–85-day slicers. More: tomato planting dates by zone.

How long is the growing season in Tracy?

About 272 days without a 32°F frost in a typical (median) year. In 9 years out of 10 the season lasts at least 228 days, and in 1 year in 10 it runs 306 days or more. In fall there is a 10% chance of frost by Nov 8 and a 30% chance by Nov 20. That ranks 76th longest of 84 California cities on this site.

When should I plant a fall garden in Tracy?

Count back from the first fall frost (Nov 20): transplant broccoli Aug 28 – Sep 11; sow kale Sep 11 – Oct 9; sow lettuce Sep 11 – Oct 9; sow radishes Oct 9 – Nov 6. Hardy crops keep growing through light frosts; the median 28°F hard freeze here is Dec 11. How the math works: succession and fall planting.

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

No. Going by the zone that covers most of the city's land, Tracy 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 Tracy compare with Manteca, CA?

Both are in zone 9b. The typical last spring frost in Tracy (Mar 9) comes about 20 days later than in Manteca, CA (Feb 17), 13 miles away, and the first fall frost is Nov 20 versus Nov 24. The two cities use different NOAA stations.