When to Plant Green Beans in California: Planting Months by Region
What California’s extension calendar says about green beans, copied region by region, plus the frost record at Sacramento Executive Airport, Santa Rosa Sonoma County Airport, and Imperial County Airport.
Updated
Figures checked against their sources on ; next check .
The green bean entry under the heading “beans, snap” in California’s calendar is read across 4 regions. This calendar is coarser than most: North & North Coast (July; May–June), South Coast (March–Aug), Interior Valleys (April–May; July–Aug), and Desert Valleys (Jan–March; Aug). The page’s note says planting dates are for seed unless noted otherwise.
Green Beans: the California table
The page files green beans as a warm-season crop.
| Region | Recommended planting months |
|---|---|
| North & North Coast | July; May–June |
| South Coast | March–Aug |
| Interior Valleys | April–May; July–Aug |
| Desert Valleys | Jan–March; Aug |
How the California calendar is built
The UC Master Gardener Program’s planting table covers four regions: North and North Coast (Monterey County north), South Coast (San Luis Obispo County south), the Interior Valleys and the Desert Valleys (Imperial and Coachella). It adds that because the areas are large, the dates are only approximate and the climate may vary even in small sections of the state.
Do green beans get an indoor start?
The general sources have little to say about starting green beans indoors, since UNH has them go straight into the ground.
UNH lists beans as a seed crop sown after the last frost, with no indoor start, so the saved sources give no seed-starting weeks for beans at all.
UNH’s own timing for green beans is after the last frost, so California’s printed window and UNH’s rule of thumb can be set side by side.
| Source | What it says |
|---|---|
| University of New Hampshire | Not started indoors; sow seed after the last frost |
Typical frost dates at California stations
Each date below is NOAA’s 50% level, meaning the last spring 32°F night lands on or after it in half the years, and the first fall night lands on or before it in half. The tool linked beside each city shows the other nine levels.
A station is tied to a region of the calendar only where the source’s own wording makes that call; the rest are left blank on purpose.
| Station | Last spring 32°F | First fall 32°F | Region in California’s calendar |
|---|---|---|---|
| Sacramento Executive Airport, California | February 2 | December 2 | Interior Valleys |
| Santa Rosa Sonoma County Airport, California | March 2 | November 20 | North & North Coast |
| Imperial County Airport, California | January 14 | December 24 | Desert Valleys |
Worked example
Pick Santa Rosa Sonoma County Airport, California as the garden. Half of recent years saw their last spring 32°F night by March 2, and half saw their first fall one by November 20.
North & North Coast’s entry reads “July; May–June”, which is an offset or a month range rather than a pair of dates, so the example stops at the frost date.
None of this predicts next spring. It only lines up two published sets of dates; swap in your own station from the frost dates tool and the same steps apply.
Before you rely on these dates
The page suggests contacting experienced gardeners in your community to find more precise dates.
Weather in the week of planting matters more than the printed date; use it to nudge the start earlier or later.
Sources (3)
- UC Master Gardener Program, University of California Agriculture and Natural Resources, Time of planting (table adapted from the California Master Gardener Handbook, Table 13.2) ucanr.edu
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991-2020, annual and seasonal normals (frost/freeze probabilities by station) ncei.noaa.gov
- University of New Hampshire Cooperative Extension, Growing Vegetables: When to Plant Your Vegetable Garden (fact sheet) extension.unh.edu