When to plant in Brea, CA
USDA Zone 10aEverything below — frost dates, hardiness zone, and what to plant when in Brea, California — is derived from the closest NOAA station with complete climate normals.
With about 354 frost-free days, Brea supports back-to-back plantings; stagger sowings every few weeks to keep beds productive spring through fall. These dates come from a station roughly 20 km away, the closest with full normals; terrain around Brea (elevation, water, pavement) can move your real frost dates a few days either way. Zone 10a is warm enough that Brea can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.
Frost probability
POMONA/FAIRPLEX · 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 Brea’s own odds, recorded at POMONA/FAIRPLEX.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | Mar 9 | Feb 8 | Dec 29 | Nov 21 | Dec 10 | Dec 26 |
| 32°F | Feb 18 | Jan 8 | Dec 14 | Dec 5 | Dec 28 | Feb 2 |
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 Brea, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 27 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.
Brea planting FAQ
When is the last spring frost in Brea, CA?
Brea's average last spring frost falls near January 8 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.
When is the first fall frost in Brea, CA?
The first fall frost in Brea typically arrives around December 28 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Brea in?
Brea is in USDA hardiness zone 10a. In zone 10a, winters are mild — many tender perennials overwinter here.
How long is the growing season in Brea?
There are roughly 354 frost-free days in Brea (a long growing season), running from the average last frost around January 8 to the first fall frost near December 28.
When should I plant tomatoes in Brea?
In Brea, start tomato seeds indoors around November 13–November 27, then transplant seedlings outdoors around January 15 once the danger of frost has passed.
Never miss a window in Brea
An email when it’s time to start seeds, transplant, and sow — timed to Brea’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Placentia · 5 km
- Rowland Heights · 6 km
- Fullerton · 7 km
- La Habra · 8 km
- Yorba Linda · 9 km
- Diamond Bar · 10 km
- South San Jose Hills · 10 km
- Walnut · 12 km
Frost dates recorded at POMONA/FAIRPLEX, 20 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 Brea, CA — Frost Dates & Zone 10a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00047050. Retrieved from https://blissgarden.com/california/brea.