Newport Beach, California: planting zone & frost dates
Newport Beach is in USDA plant hardiness zone 10b, where the average coldest winter night reaches 35 to 40°F (1.7 to 4.4°C). Frost is rare here.
Frost dates
Frost data comes from NOAA station NEWPORT BEACH HARBOR, CA (USC00046175), 0.6 mi (0.9 km) from the city center and 3 ft lower than the city center (-1 m). Record used for the 1991–2020 normals: 20 years.
Why your yard may differ from the station: microclimates.
Hardiness zone across Newport Beach
All 6 ZIP codes covering Newport Beach are in zone 10b.
Vegetable planting calendar for Newport Beach
Windows below are for a frost-free climate: plant cool-season crops from fall through late winter and warm-season crops in late winter–spring, with a second warm-season round in late summer for some crops.
| Crop | Planting windows (frost-free climate) | |||
|---|---|---|---|---|
| Tomato | Jan 15 – Mar 31; Aug 1 – Sep 15 | |||
| Pepper | Feb 1 – Apr 15; Jul 15 – Aug 31 | |||
| Lettuce | Sep 15 – Feb 15 | |||
| Green Beans | Feb 15 – Apr 30; Aug 15 – Sep 30 | |||
| Sweet Corn | Feb 15 – Apr 15; Aug 1 – Aug 31 | |||
| Zucchini & Summer Squash | Feb 15 – Apr 15; Aug 1 – Sep 15 | |||
| Cucumber | Feb 15 – Apr 15; Aug 1 – Sep 15 | |||
| Carrot | Sep 1 – Feb 28 | |||
| Onion | Oct 15 – Jan 15 | |||
| Potato | Jan 1 – Feb 28; Sep 1 – Oct 15 | |||
| Basil | Mar 1 – Jun 30; Aug 15 – Sep 30 | |||
| Spinach | Oct 1 – Feb 15 | |||
| Kale | Sep 1 – Feb 15 | |||
| Broccoli | Sep 1 – Jan 15 | |||
| Peas | Oct 1 – Jan 31 | |||
| Eggplant | Feb 15 – Apr 30; Jul 15 – Aug 31 | |||
| Cabbage | Sep 1 – Jan 31 | |||
| Radish | Sep 15 – Mar 15 | |||
| Strawberry | Oct 1 – Nov 30 | |||
| Beets | Sep 15 – Feb 28 | |||
Nearby cities in California
- Costa Mesa — zone 10b, frost rare
- Santa Ana — zone 10b, frost rare
- Irvine — zone 10b, last frost Jan 14, first frost Dec 13
- Huntington Beach — zone 10b, frost rare
- Tustin — zone 10a, frost rare
- Westminster — zone 10a, frost rare
More: all California cities · other zone 10b cities: San Diego, CA, San Francisco, CA, Long Beach, CA, Anaheim, CA, Irvine, CA, Santa Ana, CA, Chula Vista, CA, St. Petersburg, FL
Newport Beach gardening questions
Does it ever frost in Newport Beach, CA?
Rarely. From 1991 to 2020, NOAA's Newport Beach Harbor, CA station, 0.6 mi from the city center, did not reach 32°F at all — too seldom for NOAA to compute frost dates. Zone 10b means the coldest night of an average winter is 35 to 40°F (1.7 to 4.4°C), so frost is essentially unknown, though cool nights can slow tropical plants.
When should I plant tomatoes in Newport Beach, CA?
Without a frost season, plant by temperature: set out tomatoes Jan 15 – Mar 31 and Aug 1 – Sep 15. Fruit set drops when nights stay above about 75°F, so avoid timing harvests for the hottest weeks. More: tomato planting by zone.
When is the best time for lettuce and broccoli in Newport Beach?
Cool-season crops do best in the mild months: plant lettuce Sep 15 – Feb 15 and broccoli Sep 1 – Jan 15. Summer heat makes lettuce bolt and broccoli flower early.
Did Newport Beach's hardiness zone change on the 2023 map?
Yes. Most of Newport Beach was zone 10a on the 2012 map and is zone 10b on the 2023 map — half a zone warmer, like about 56% of U.S. ZIP codes. The shift comes from a newer 1991–2020 averaging period plus more weather stations and better mapping; it does not mean last frost comes earlier. Why the 2023 map is warmer.
How does Newport Beach compare with Costa Mesa, CA?
Both are in zone 10b. Frost is rare in both Newport Beach and Costa Mesa, CA (5 miles away), so both garden year-round.