When to plant in Montclair, CA
USDA Zone 10aEverything below — frost dates, hardiness zone, and what to plant when in Montclair, California — is derived from the closest NOAA station with complete climate normals.
With about 354 frost-free days, Montclair supports back-to-back plantings; stagger sowings every few weeks to keep beds productive spring through fall. Zone 10a is warm enough that Montclair 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 Montclair’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 Montclair, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 12 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.
Montclair planting FAQ
When is the last spring frost in Montclair, CA?
Montclair'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 Montclair, CA?
Expect Montclair's first fall frost near December 28 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.
What hardiness zone is Montclair in?
Montclair is in USDA hardiness zone 10a. In zone 10a, winters are mild — many tender perennials overwinter here.
How long is the growing season in Montclair?
There are roughly 354 frost-free days in Montclair (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 Montclair?
In Montclair, 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 Montclair
An email when it’s time to start seeds, transplant, and sow — timed to Montclair’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reachFrost dates recorded at POMONA/FAIRPLEX, 6 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 Montclair, CA — Frost Dates & Zone 10a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00047050. Retrieved from https://blissgarden.com/california/montclair.