FrostCal

When to Plant Zinnias in California

In a typical California location, start seeds indoors Dec 19 – Dec 26, then sow outdoors Jan 23 – Feb 6, then transplant outdoors Jan 23 – Jan 30. Across the state, the outdoor planting window starts as early as Jan 5 in San Mateo and as late as Jun 3 in Big Bear City. 103 cities in California are essentially frost-free and can plant on a year-round schedule.

Method Direct sow
Days to maturity 60–70 days

Frost-tender; direct sow 1-3 weeks after last frost, or start indoors 3-4 weeks early for earlier blooms.

Zinnias Planting Dates by City

CityStart indoorsDirect sowTransplant
Los AngelesFrost-free: year-round planting
San DiegoFrost-free: year-round planting
San JoseDec 5 – Dec 12Jan 9 – Jan 23Jan 9 – Jan 16
San FranciscoFrost-free: year-round planting
FresnoDec 17 – Dec 24Jan 21 – Feb 4Jan 21 – Jan 28
SacramentoDec 15 – Dec 22Jan 19 – Feb 2Jan 19 – Jan 26
Long BeachFrost-free: year-round planting
OaklandFrost-free: year-round planting
BakersfieldJan 3 – Jan 10Feb 7 – Feb 21Feb 7 – Feb 14
AnaheimFrost-free: year-round planting
RiversideDec 12 – Dec 19Jan 16 – Jan 30Jan 16 – Jan 23
Santa AnaFrost-free: year-round planting
StocktonJan 8 – Jan 15Feb 12 – Feb 26Feb 12 – Feb 19
Chula VistaFrost-free: year-round planting
IrvineFrost-free: year-round planting
FremontDec 10 – Dec 17Jan 14 – Jan 28Jan 14 – Jan 21
San BernardinoDec 30 – Jan 6Feb 3 – Feb 17Feb 3 – Feb 10
FontanaDec 13 – Dec 20Jan 17 – Jan 31Jan 17 – Jan 24
ModestoJan 3 – Jan 10Feb 7 – Feb 21Feb 7 – Feb 14
OxnardFrost-free: year-round planting
Moreno ValleyDec 30 – Jan 6Feb 3 – Feb 17Feb 3 – Feb 10
Huntington BeachFrost-free: year-round planting
GlendaleDec 5 – Dec 12Jan 9 – Jan 23Jan 9 – Jan 16
Santa ClaritaDec 11 – Dec 18Jan 15 – Jan 29Jan 15 – Jan 22
Santa RosaJan 28 – Feb 4Mar 4 – Mar 18Mar 4 – Mar 11
OceansideFrost-free: year-round planting
Garden GroveFrost-free: year-round planting
Rancho CucamongaDec 7 – Dec 14Jan 11 – Jan 25Jan 11 – Jan 18
OntarioDec 7 – Dec 14Jan 11 – Jan 25Jan 11 – Jan 18
Elk GroveJan 5 – Jan 12Feb 9 – Feb 23Feb 9 – Feb 16

Showing the 30 most populous of 530 California cities. Dates are estimates from each city's NOAA frost normals and university extension timing guidelines. See all California cities.

Frequently Asked Questions

When should I plant zinnias in California?

In a typical California location, start seeds indoors Dec 19 – Dec 26, then sow outdoors Jan 23 – Feb 6, then transplant outdoors Jan 23 – Jan 30. Across the state, the outdoor planting window starts as early as Jan 5 in San Mateo and as late as Jun 3 in Big Bear City. 103 cities in California are essentially frost-free and can plant on a year-round schedule.

When is the last frost in California?

The average last spring frost in California ranges from January 1 in Palm Springs to December 31 in Sunland, based on NOAA 1991–2020 climate normals.

How long do zinnias take to grow?

Zinnias typically take 60–70 days from planting to harvest. Frost-tender; direct sow 1-3 weeks after last frost, or start indoors 3-4 weeks early for earlier blooms.

Other Crops in California

When to plant zinnias in other states

Related Guides