When to plant in Modesto, CA
USDA Zone 9bModesto, California frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.
A generous ~308-day season lets Modesto gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. In zone 9b, frost is a minor factor for Modesto — most perennials thrive, and annual vegetables can go out early and stay late.
The average first fall frost in Modesto is now 7 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →
Frost probability
MODESTO CITY CO AP · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Modesto’s own odds, recorded at MODESTO CITY CO AP.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | Mar 31 | Mar 1 | Feb 3 | Nov 8 | Nov 22 | Dec 9 |
| 32°F | Feb 25 | Jan 31 | Dec 31 | Nov 20 | Dec 5 | Jan 6 |
| 28°F | Feb 6 | Jan 8 | Dec 16 | Dec 1 | Dec 21 | Jan 20 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Modesto, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 31 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
Modesto planting FAQ
When is the last spring frost in Modesto, CA?
On average, the last spring frost in Modesto is around January 31 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.
When is the first fall frost in Modesto, CA?
The first fall frost in Modesto typically arrives around December 5 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Modesto in?
Modesto is in USDA hardiness zone 9b. In zone 9b, winters are mild — many tender perennials overwinter here.
How long is the growing season in Modesto?
Modesto has about 308 frost-free days — a long growing season — between the average last spring frost (January 31) and first fall frost (December 5).
When should I plant tomatoes in Modesto?
For Modesto, sow tomatoes indoors about December 6–December 20 and move the seedlings out around February 7, after the last spring frost.
Never miss a window in Modesto
An email when it’s time to start seeds, transplant, and sow — timed to Modesto’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reachFrost dates recorded at MODESTO CITY CO AP, 5 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Modesto, CA — Frost Dates & Zone 9b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00023258. Retrieved from https://blissgarden.com/california/modesto.