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California planting dates
When to Plant Onions in California
For onions in California, spring planting starts between Aug 1 (Butte County) and Apr 1 (Alameda County); fall planting starts between Sep 1 (Imperial County) and Nov 1 (Alameda County), according to UC Master Gardener Program.
Photo: Long rows of green onion plants growing in sandy farm soil. ליזי שאנן, CC BY 2.5, via Wikimedia Commons
Onions planting window by county
The UC table gives separate dates for the coast, the interior valleys and the desert valleys; each county uses its region.
Published dates for onions in California
| Type | Season | Region | Published dates | Source |
|---|---|---|---|---|
| Onions, green | spring | North & North Coast | April-July | California Master Gardener Handbook Table 13.2, Table 'Recommended planting dates' (California Master Gardener Handbook Table 13.2) |
| Onions, bulb | fall | Desert Valleys | Oct-Nov | California Master Gardener Handbook Table 13.2, Table 'Recommended planting dates' (California Master Gardener Handbook Table 13.2) |
| Onions, green | fall | Desert Valleys | Sept-Jan | California Master Gardener Handbook Table 13.2, Table 'Recommended planting dates' (California Master Gardener Handbook Table 13.2) |
| Onions, bulb | fall | Interior Valleys | Oct-Nov | California Master Gardener Handbook Table 13.2, Table 'Recommended planting dates' (California Master Gardener Handbook Table 13.2) |
| Onions, bulb | winter | Interior Valleys | Jan-March | California Master Gardener Handbook Table 13.2, Table 'Recommended planting dates' (California Master Gardener Handbook Table 13.2) |
| Onions, green | summer | Interior Valleys | Aug-Dec | California Master Gardener Handbook Table 13.2, Table 'Recommended planting dates' (California Master Gardener Handbook Table 13.2) |
| Onions, bulb | winter | North & North Coast | Jan-March | California Master Gardener Handbook Table 13.2, Table 'Recommended planting dates' (California Master Gardener Handbook Table 13.2) |
| Onions, bulb | fall | North & North Coast | Nov-Jan | California Master Gardener Handbook Table 13.2, Table 'Recommended planting dates' (California Master Gardener Handbook Table 13.2) |
| Onions, bulb | winter | South Coast | Feb-Oct | California Master Gardener Handbook Table 13.2, Table 'Recommended planting dates' (California Master Gardener Handbook Table 13.2) |
| Onions, green | all year | South Coast | all year | California Master Gardener Handbook Table 13.2, Table 'Recommended planting dates' (California Master Gardener Handbook Table 13.2) |
Planting dates for onions by California county
| County | Spring | Summer and fall |
|---|---|---|
| Alameda | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Alpine | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Amador | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Butte | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| Calaveras | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Colusa | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| Contra Costa | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Del Norte | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| El Dorado | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Fresno | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| Glenn | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| Humboldt | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Imperial | n/a | Oct 1 to Nov 30; Sep 1 to Jan 31 |
| Inyo | n/a | Oct 1 to Nov 30; Sep 1 to Jan 31 |
| Kern | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| Kings | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| Lake | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Lassen | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Los Angeles | Feb 1 to Oct 31; Jan 1 to Dec 31 | n/a |
| Madera | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| Marin | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Mariposa | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Mendocino | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Merced | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| Modoc | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Mono | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Monterey | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Napa | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Nevada | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Orange | Feb 1 to Oct 31; Jan 1 to Dec 31 | n/a |
| Placer | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| Plumas | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Riverside | n/a | Oct 1 to Nov 30; Sep 1 to Jan 31 |
| Sacramento | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| San Benito | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| San Bernardino | n/a | Oct 1 to Nov 30; Sep 1 to Jan 31 |
| San Diego | Feb 1 to Oct 31; Jan 1 to Dec 31 | n/a |
| San Francisco | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| San Joaquin | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| San Luis Obispo | Feb 1 to Oct 31; Jan 1 to Dec 31 | n/a |
| San Mateo | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Santa Barbara | Feb 1 to Oct 31; Jan 1 to Dec 31 | n/a |
| Santa Clara | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Santa Cruz | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Shasta | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| Sierra | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Siskiyou | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Solano | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| Sonoma | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Stanislaus | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| Sutter | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| Tehama | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| Trinity | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Tulare | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| Tuolumne | Apr 1 to Jul 31; Jan 1 to Mar 31 | Nov 1 to Jan 31 |
| Ventura | Feb 1 to Oct 31; Jan 1 to Dec 31 | n/a |
| Yolo | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
| Yuba | Aug 1 to Dec 31; Jan 1 to Mar 31 | Oct 1 to Nov 30 |
California planting dates for other crops
- Tomatoes
- Peppers
- Potatoes
- Sweet Potatoes
- Sweet Corn
- Green Beans
- Lima Beans
- Peas
- Cucumbers
- Squash
- Winter Squash
- Pumpkins
- Watermelon
- Cantaloupe
- Okra
- Eggplant
- Lettuce
- Spinach
- Kale
- Mustard Greens
- Turnips
- Swiss Chard
- Cabbage
- Broccoli
- Cauliflower
- Brussels Sprouts
- Kohlrabi
- Carrots
- Beets
- Radishes
- Garlic
- Leeks
- Asparagus
- Rutabagas
- Parsley
More planting dates for California
Planting dates for each crop in California, from the UC Master Gardener Program calendar.
Planting onions in California: questions
When do you plant onions in California?
For onions in California, spring planting starts between Aug 1 (Butte County) and Apr 1 (Alameda County); fall planting starts between Sep 1 (Imperial County) and Nov 1 (Alameda County), according to UC Master Gardener Program.
Can I plant onions in the fall in California?
Yes. Fall planting starts between Sep 1 (Imperial County) and Nov 1 (Alameda County).
How do frost dates affect planting onions?
Yes. The California frost dates page gives the 10% and 50% dates for every county.
Where do these dates for onions come from?
California Master Gardener Handbook Table 13.2 Time of planting (UC Master Gardener Program statewide page; table 'Recommended planting dates', source: California Master Gardener Handbook, Table 13.2).
Do these dates change by county?
Dates follow the region the county is assigned to here, from the four regions in the UC table.
Photos: Long rows of green onion plants growing in sandy farm soil: ליזי שאנן, CC BY 2.5, via Wikimedia Commons; Snow-covered Mount Shasta above Lake Siskiyou and forested shore: Radomianin, CC BY-SA 4.0, via Wikimedia Commons; North face of Mount Shasta in golden evening light: Frank Schulenburg, CC BY-SA 4.0, via Wikimedia Commons; Mount Shasta above conifers and patches of spring snow at Bunny Flat: Frank Schulenburg, CC BY-SA 4.0, via Wikimedia Commons; Mount Shasta rising over open land and Highway 97: Frank Schulenburg, CC BY-SA 4.0, via Wikimedia Commons; Rocky Pacific coast with a bridge and green headlands at Big Sur: dconvertini, CC BY-SA 2.0, via Wikimedia Commons; Tomato plant with fruit in a garden: MavisLee, CC BY-SA 3.0, via Wikimedia Commons; Pepper plant in a kitchen garden loaded with green, yellow and red peppers: NPS, Public domain, via Wikimedia Commons; Potato plant growing in a garden bed: Kolforn (Kolforn), CC BY-SA 4.0, via Wikimedia Commons; Field of sweet corn in summer: Marathon, CC BY-SA 2.0, via Wikimedia Commons; Clusters of long green bean pods hanging from a climbing bean vine: Nirajan_pant, CC BY-SA 3.0, via Wikimedia Commons; Cucumber plants growing in a greenhouse bed: HARTLEPOOLMARINA2014, CC BY-SA 4.0, via Wikimedia Commons; Zucchini plant with a yellow flower: net_efekt from Oxford, UK, CC BY 2.0, via Wikimedia Commons; Young lettuce plant in garden soil: GT1976, CC BY-SA 4.0, via Wikimedia Commons.