When to plant in Stanford, CA
USDA Zone 9bStanford, 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 ~309-day season lets Stanford gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. Zone 9b is warm enough that Stanford can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.
The average last spring frost in Stanford is now 6 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →
Frost probability
PALO ALTO · 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 Stanford’s own odds, recorded at PALO ALTO.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | Apr 15 | Mar 11 | Feb 5 | Nov 3 | Nov 21 | Dec 8 |
| 32°F | Mar 4 | Feb 1 | Dec 28 | Nov 20 | Dec 7 | Jan 6 |
| 28°F | Feb 17 | Jan 4 | Dec 15 | Dec 3 | Dec 22 | Jan 25 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Nothing new to sow or transplant outdoors in the next few weeks — a seasonal lull. Check the full-year calendar below for the next window.
Full-year planting calendar
Each bar is the exact window to take a planting action in Stanford, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 8 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.
Stanford planting FAQ
When is the last spring frost in Stanford, CA?
Plan for the last spring frost in Stanford around February 1 (the date it has a 50% chance of a 32°F freeze). Anything frost-sensitive should go out after it.
When is the first fall frost in Stanford, CA?
In Stanford, the first 32°F freeze of fall lands around December 7 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is Stanford in?
Stanford is in USDA hardiness zone 9b. In zone 9b, winters are mild — many tender perennials overwinter here.
How long is the growing season in Stanford?
There are roughly 309 frost-free days in Stanford (a long growing season), running from the average last frost around February 1 to the first fall frost near December 7.
When should I plant tomatoes in Stanford?
In Stanford, start tomato seeds indoors around December 7–December 21, then transplant seedlings outdoors around February 8 once the danger of frost has passed.
Never miss a window in Stanford
An email when it’s time to start seeds, transplant, and sow — timed to Stanford’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Palo Alto · 4 km
- East Palo Alto · 6 km
- Menlo Park · 6 km
- North Fair Oaks · 6 km
- Mountain View · 8 km
- Los Altos · 9 km
- Redwood City · 11 km
- San Carlos · 12 km
Frost dates recorded at PALO ALTO, 3 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 Stanford, CA — Frost Dates & Zone 9b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00046646. Retrieved from https://blissgarden.com/california/stanford.