When to plant in Belmont, CA

Planting dates worked out from Belmont's own frost records, not a generic zone chart.

Frost is rare in Belmont: in 8 of the last 26 springs there was none at all. Frost dates matter less here than heat, so the planting table below is left out.

Safe to plant out

Feb 22

1 year in 10 has a later frost

Average last frost

Jan 23

about a 50% chance of a later one

Average first fall frost

Dec 14

1 year in 10 by Nov 25

Frost-free days

324

median, 1991–2020

Station used: Redwood City · 5.8 km away · station 9 m, town 13 m. How we match towns to stations

Belmont's weather over time

How the growing season has shifted here, year by year, from the station's own records.

Each year's last spring frostLong-term trend

See the data as a table

Year	Last spring frost
1931	Apr 3
1932	Mar 4
1933	Apr 18
1934	Jan 12
1935	Mar 11
1936	Feb 8
1937	Feb 27
1938	Feb 17
1939	Mar 1
1940	Jan 21
1942	Jan 4
1943	Feb 10
1945	Jan 24
1946	Feb 14
1947	Feb 1
1948	Mar 4
1949	Feb 14
1950	Mar 13
1951	Mar 11
1952	Jan 9
1953	Mar 3
1954	Jan 25
1955	Feb 28
1956	Feb 17
1957	Feb 5
1958	Jan 7
1959	Feb 13
1960	Jan 17
1961	Jan 21
1962	Feb 28
1963	Jan 22
1964	Mar 25
1965	Feb 12
1966	Mar 17
1967	Mar 5
1968	Jan 28
1969	Feb 3
1970	Jan 6
1971	Mar 6
1972	Feb 2
1973	Feb 1
1974	Feb 7
1975	Feb 23
1976	Mar 9
1977	Mar 14
1979	Feb 4
1980	Jan 30
1981	Feb 3
1982	Jan 11
1983	Jan 20
1984	Jan 18
1985	Feb 10
1987	Jan 21
1988	Feb 6
1989	Feb 14
1990	Feb 20
1991	Jan 30
1992	Jan 25
1993	Jan 5
1994	Feb 13
1996	Feb 26
1997	Jan 14
2001	Feb 9
2003	Feb 10
2004	Jan 21
2007	Feb 2
2009	Jan 27
2011	Feb 27
2012	Jan 18
2013	Feb 20
2015	Jan 3
2017	Jan 6
2018	Feb 24
2019	Feb 19
2022	Feb 25
2023	Feb 18
2025	Feb 10

Each year's frost-free daysLong-term trend

See the data as a table

Year	Frost-free days
1931	223
1932	277
1933	225
1934	324
1935	237
1936	273
1937	302
1938	267
1939	298
1940	305
1941	363
1942	360
1943	323
1944	363
1945	322
1946	262
1947	291
1948	268
1949	299
1950	292
1951	271
1952	318
1953	297
1954	308
1955	277
1956	277
1957	328
1958	313
1959	296
1960	323
1961	299
1962	299
1963	322
1964	236
1965	305
1966	252
1967	271
1968	308
1969	298
1970	347
1971	283
1972	305
1973	332
1974	318
1975	268
1976	263
1977	291
1978	316
1979	289
1980	334
1981	330
1982	332
1983	344
1984	332
1985	275
1986	363
1987	337
1988	322
1989	300
1990	286
1991	318
1992	326
1993	322
1994	278
1995	363
1996	292
1997	342
1998	339
1999	348
2003	323
2004	312
2007	313
2009	312
2010	326
2011	281
2012	334
2013	286
2014	363
2015	327
2016	350
2017	349
2018	309
2019	314
2020	362
2021	363
2022	279
2023	315
2024	363
2025	323

Each year's average temperature, April to SeptemberLong-term trend

See the data as a table

Year	Growing-season temperature
1931	17.9 °C
1932	16.6 °C
1933	16.0 °C
1934	17.8 °C
1935	17.4 °C
1936	18.3 °C
1937	17.5 °C
1938	18.1 °C
1939	18.4 °C
1940	18.2 °C
1941	17.8 °C
1942	18.0 °C
1944	18.3 °C
1945	18.3 °C
1946	17.6 °C
1947	18.3 °C
1948	17.1 °C
1949	17.9 °C
1950	18.2 °C
1951	17.5 °C
1952	18.0 °C
1953	17.3 °C
1954	18.0 °C
1955	16.7 °C
1956	17.4 °C
1957	18.5 °C
1958	18.9 °C
1959	19.1 °C
1960	18.4 °C
1961	18.9 °C
1962	18.0 °C
1963	18.2 °C
1964	17.7 °C
1965	17.8 °C
1966	18.8 °C
1967	17.9 °C
1968	18.2 °C
1969	18.3 °C
1970	18.3 °C
1971	17.9 °C
1972	18.5 °C
1973	18.8 °C
1974	18.3 °C
1975	17.5 °C
1976	18.4 °C
1977	18.1 °C
1978	18.7 °C
1979	18.8 °C
1980	18.1 °C
1981	19.2 °C
1983	18.9 °C
1984	19.2 °C
1985	18.4 °C
1986	17.9 °C
1987	18.4 °C
1988	18.5 °C
1989	18.4 °C
1990	18.8 °C
1991	17.6 °C
1992	19.3 °C
1993	19.1 °C
1994	18.1 °C
1995	18.2 °C
1996	18.6 °C
1997	19.3 °C
1998	17.7 °C
1999	17.4 °C
2002	18.0 °C
2003	18.8 °C
2004	18.8 °C
2007	18.6 °C
2009	18.5 °C
2010	17.1 °C
2011	17.5 °C
2012	17.9 °C
2013	19.0 °C
2014	19.3 °C
2015	19.1 °C
2016	18.6 °C
2017	19.2 °C
2018	18.1 °C
2019	19.0 °C
2020	19.5 °C
2021	18.3 °C
2022	18.9 °C
2023	18.1 °C
2024	18.8 °C
2025	18.6 °C
2026	18.7 °C

What this means for you: Since 1931, Belmont's last spring frost has come about 2 days earlier per decade, on average. The frost-free season has grown by about 5 days per decade. Year-to-year swings are large, so keep using the safe date rather than the trend.

Source: daily records from Redwood City (NOAA GHCN-Daily). Years with too many missing days are left out.

Nearby towns

San Carlos Foster City Redwood City Highlands-Baywood Park Emerald Lake Hills San Mateo