San Bernardino, California planting calendar and frost dates
San Bernardino is in USDA hardiness zone 10a. The last spring frost typically comes around January 27 and the first fall frost around December 19, giving about 329 frost-free days a year.
- Typical last frost
- January 27
- Typical first frost
- December 19
- Frost-free season
- 329 days
Frost dates in San Bernardino
Last spring frost
- December 21Risky: frost later than this in 9 years out of 10
- January 27Typical: a later frost in half of years
- February 28Safe: a later frost only 1 year in 10
First fall frost
- December 1Risky: frost earlier than this 1 year in 10
- December 19Typical: an earlier frost in half of years
- New yearLate: in about 1 year in 10, the first frost waits until after December 31
The growing season between the typical last and first frosts is about 329 days. Frost here means a low of 32°F at the weather station.
NOAA U.S. Climate Normals 1991-2020 for Redlands, 7.3 miles SE of the city center and 359 feet higher. Low-lying and rural spots often frost later in spring and earlier in fall than airports and city centers.
What to plant each month in San Bernardino
January
Start indoors: ginger, peppers, ranunculus
Plant or sow outdoors: asparagus, avocados, beets, black-eyed susans, blackberries, broccoli, cabbages, carrots, cauliflower, chives, cilantro, collard greens, dahlias, dill, figs, garden mums, gladioli, grapes, green onions, lavenders, leeks, lettuce, lilies, marigolds, mints, nasturtiums, onions, oregano, parsley, petunias, potatoes, radishes, ranunculus, rosemary, roses, sage, snapdragons, spinach, sunflowers, sweet corn, swiss chard, thyme, turnips
Plant for fall: crocuses, garlic, hyacinths, ornamental alliums, tulips
February
Start indoors: basil, celery, eggplants, peppers, tomatoes
Plant or sow outdoors: avocados, chives, cilantro, dahlias, dill, garden mums, ginger, gladioli, grapes, green onions, lavenders, lettuce, lilies, marigolds, mints, nasturtiums, oregano, parsley, petunias, ranunculus, rosemary, sage, spinach, sunflowers, sweet corn, swiss chard, thyme
March
Start indoors: basil, cantaloupes, cosmos, cucumbers, okra, pumpkins, watermelons, winter squash, zucchini
Plant or sow outdoors: ginger, st. augustinegrass
April
Plant or sow outdoors: basil, cantaloupes, cucumbers, eggplants, green beans, peppers, pumpkins, st. augustinegrass, tomatoes, watermelons, winter squash, zucchini
May
Start indoors: zinnias
Plant or sow outdoors: bermudagrass, celery, centipedegrass, cosmos, okra, peanuts, sweet potatoes, zoysiagrass
June
Plant or sow outdoors: bermudagrass, centipedegrass, zinnias, zoysiagrass
August
September
Plant for fall: bearded irises, brussels sprouts, carrots, collard greens, cucumbers, green beans, lettuce, peas, peppers, potatoes, snapdragons, sweet corn, swiss chard, tomatoes, zucchini
October
Start indoors: onions
Plant for fall: azaleas, bearded irises, beets, broccoli, cabbages, carrots, cauliflower, clematis, collard greens, coneflowers, cucumbers, daylilies, green beans, hostas, hydrangeas, kale, lettuce, peas, radishes, roses, saffron, snapdragons, spinach, swiss chard, turnips, zucchini
November
Start indoors: broccoli, cabbages, cauliflower, collard greens, kale, leeks, onions, oregano, parsley, petunias, ranunculus, rosemary, snapdragons
Plant for fall: azaleas, bearded irises, cabbages, cauliflower, clematis, coneflowers, crocuses, daffodils, daylilies, grass seed, hostas, hyacinths, hydrangeas, kale, kentucky bluegrass, lilies, ornamental alliums, peonies, perennial ryegrass, radishes, roses, saffron, spinach, tall fescue, tulips
December
Start indoors: black-eyed susans, broccoli, cabbages, cauliflower, chives, cilantro, collard greens, ginger, leeks, lettuce, marigolds, nasturtiums, oregano, parsley, petunias, ranunculus, rosemary, sage, snapdragons, spinach, swiss chard
Plant or sow outdoors: asparagus, beets, black-eyed susans, blackberries, blueberries, broccoli, cauliflower, chives, cilantro, collard greens, figs, garlic, gladioli, grapes, grass seed, green onions, hollyhocks, kale, kentucky bluegrass, leeks, onions, peas, poppies, radishes, ranunculus, raspberries, rhubarb, roses, spinach, strawberries, sweet peas, swiss chard, tall fescue, turnips, wildflowers
Plant for fall: crocuses, daffodils, garlic, hyacinths, lilies, ornamental alliums, peonies, tulips
Frost dates and zones by ZIP code in San Bernardino
All 7 of San Bernardino's main ZIP codes take their frost dates from Redlands, so the dates on this page apply across the city. Every one of them is in zone 10a.
| ZIP code | Zone | Weather station | Typical last frost | Typical first frost |
|---|---|---|---|---|
| 92346 | 10a | Redlands, 7.3 mi SE | Jan 27 | Dec 19 |
| 92404 | 10a | Redlands, 7.3 mi SE | Jan 27 | Dec 19 |
| 92405 | 10a | Redlands, 7.3 mi SE | Jan 27 | Dec 19 |
| 92407 | 10a | Redlands, 7.3 mi SE | Jan 27 | Dec 19 |
| 92408 | 10a | Redlands, 7.3 mi SE | Jan 27 | Dec 19 |
| 92410 | 10a | Redlands, 7.3 mi SE | Jan 27 | Dec 19 |
| 92411 | 10a | Redlands, 7.3 mi SE | Jan 27 | Dec 19 |
Redlands also supplies the frost dates for Moreno Valley, Rialto, Perris, Redlands, Highland and Yucaipa and 1 more cities, so their planting calendars match San Bernardino's.
Planting dates for popular crops in San Bernardino
| Plant | Start indoors | Plant or sow outdoors | Fall planting |
|---|---|---|---|
| Tomatoes | Feb 8 to 22 | Apr 5 to 19 | Sep 5 to 12 |
| Strawberries | — | Dec 16 to 30 | — |
| Lettuce | Dec 2 to 16 | Jan 20 to Feb 3 | Sep 19 to Oct 24 |
| Cilantro | Dec 16 to 30 | Jan 27 to Feb 3 | — |
| Basil | Feb 15 to Mar 1 | Apr 5 to 12 | — |
| Potatoes | — | Jan 6 to 13 | Aug 29 to Sep 5 |
| Garlic | — | Dec 16 to 30 | Dec 19 to Jan 2 |
| Onions | Oct 7 to Nov 18 | Dec 30 to Jan 13 | — |
| Cucumbers | Mar 8 to 22 | Apr 5 to 19 | Sep 19 to Oct 3 |
| Pumpkins | Mar 8 to 22 | Apr 5 to 19 | — |
| Peppers | Jan 18 to Feb 15 | Apr 5 to 19 | Aug 29 to Sep 26 |
| Carrots | — | Jan 6 to 27 | Sep 26 to Oct 17 |
| Sweet Potatoes | — | May 7 to 14 | — |
| Watermelons | Mar 1 to 15 | Apr 5 to 19 | — |
| Sweet Corn | — | Jan 27 to Feb 10 | Sep 12 to 26 |
| Green Beans | — | Apr 5 to 19 | Sep 26 to Oct 3 |
| Zucchini | Mar 8 to 22 | Apr 5 to 19 | Sep 26 to Oct 10 |
| Broccoli | Nov 11 to Dec 2 | Dec 30 to Jan 13 | Oct 3 to 31 |
| Peas | — | Dec 16 to 30 | Sep 26 to Oct 10 |
| Spinach | Dec 16 to 23 | Jan 20 to Feb 3 | Oct 10 to Nov 14 |
| Sunflowers | — | Jan 27 to Feb 17 | — |
| Zinnias | May 10 to 17 | Jun 7 to 21 | — |
| Tulips | — | — | Nov 7 to Jan 2 |
| Daffodils | — | — | Nov 7 to Dec 19 |
| Grass Seed | — | Dec 16 to 30 | Nov 7 to 21 |
Nearby cities
- Rialto, CA zone 10a, last frost Jan 27
- Colton, CA zone 10a, last frost Jan 27
- Highland, CA zone 10a, last frost Jan 27
- Redlands, CA zone 9b, last frost Jan 27
- Fontana, CA zone 10a, last frost Jan 9
- Jurupa Valley, CA zone 10a, last frost Jan 9
Planting in CaliforniaAbout zone 10aPrintable calendar for San Bernardino
Questions
When is the last frost in San Bernardino?
Around January 27 in a typical year, based on NOAA's 1991-2020 records for Redlands. There is still a 1 in 10 chance of frost after February 28.
What planting zone is San Bernardino in?
USDA hardiness zone 10a (2023 map), with parts of the city in zone 8a. The zone tells you which perennials survive the winter; planting dates depend on frost dates instead.
When should I plant tomatoes in San Bernardino?
Start seeds indoors February 8 to 22 and set plants out April 5 to 19.
When is the first frost in San Bernardino?
Around December 19 in a typical year, and before December 1 about 1 year in 10.