When to plant in El Cajon, CA
USDA Zone 10aEl Cajon, 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 ~349-day season lets El Cajon gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. Zone 10a is warm enough that El Cajon can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.
The average last spring frost in El Cajon is now 6 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →
Frost probability
EL CAJON · 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 El Cajon’s own odds, recorded at EL CAJON.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | Mar 3 | Feb 6 | Jan 6 | Nov 18 | Dec 6 | Dec 29 |
| 32°F | Feb 7 | Jan 6 | Dec 13 | Dec 1 | Dec 21 | Jan 15 |
| 28°F | Jan 15 | Dec 31 | Dec 8 | Dec 7 | Dec 30 | Jan 14 |
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 El Cajon, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 18 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.
El Cajon planting FAQ
When is the last spring frost in El Cajon, CA?
El Cajon's average last spring frost falls near January 6 — 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 El Cajon, CA?
In El Cajon, the first 32°F freeze of fall lands around December 21 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is El Cajon in?
El Cajon is in USDA hardiness zone 10a. In zone 10a, winters are mild — many tender perennials overwinter here.
How long is the growing season in El Cajon?
There are roughly 349 frost-free days in El Cajon (a long growing season), running from the average last frost around January 6 to the first fall frost near December 21.
When should I plant tomatoes in El Cajon?
In El Cajon, start tomato seeds indoors around November 11–November 25, then transplant seedlings outdoors around January 13 once the danger of frost has passed.
Never miss a window in El Cajon
An email when it’s time to start seeds, transplant, and sow — timed to El Cajon’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Bostonia · 3 km
- Casa de Oro-Mount Helix · 4 km
- Winter Gardens · 5 km
- Rancho San Diego · 6 km
- Santee · 6 km
- La Mesa · 7 km
- Lakeside · 8 km
- Spring Valley · 8 km
Frost dates recorded at EL CAJON, 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 El Cajon, CA — Frost Dates & Zone 10a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00042706. Retrieved from https://blissgarden.com/california/el-cajon.