When to plant in Riverside, CA

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

Frost is rare in Riverside: in 11 of the last 15 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

Jan 10

1 year in 10 has a later frost

Average last frost

Jan 6

about a 50% chance of a later one

Average first fall frost

Dec 26

1 year in 10 by Dec 15

Frost-free days

359

median, 1991–2020

Station used: Riverside Fire Stn 3 · 0.8 km away · station 256 m, town 252 m. How we match towns to stations

Riverside'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
1893	Mar 12
1894	Apr 28
1895	Feb 6
1902	Mar 5
1903	Mar 19
1904	Mar 12
1905	Feb 14
1906	Apr 2
1907	Mar 28
1908	Mar 10
1910	Feb 18
1911	Feb 22
1912	Feb 26
1913	Apr 15
1914	Jan 13
1915	Jan 18
1916	Mar 25
1917	Mar 16
1918	Feb 19
1919	Mar 12
1920	Mar 28
1921	Apr 6
1922	Apr 10
1923	Mar 5
1924	Mar 22
1925	Mar 13
1926	Jan 28
1927	Jan 25
1928	Mar 18
1929	Apr 10
1930	Mar 1
1931	Mar 10
1932	Apr 22
1933	Mar 26
1934	Feb 1
1935	Mar 25
1936	Mar 27
1937	Mar 19
1938	Mar 30
1939	Mar 7
1940	Mar 13
1941	Jan 3
1942	Mar 27
1943	Feb 10
1944	Mar 29
1945	Apr 5
1946	Mar 15
1949	Mar 30
1950	Mar 16
1951	Mar 11
1952	Mar 9
1953	Apr 12
1954	Mar 26
1955	Apr 5
1956	Mar 13
1957	Feb 5
1958	Mar 3
1959	Feb 14
1960	Jan 18
1961	Jan 8
1962	Mar 15
1963	Mar 5
1964	Mar 9
1965	Feb 18
1966	Mar 4
1967	Jan 2
1968	Jan 30
1969	Feb 1
1970	Apr 4
1971	Mar 3
1972	Jan 31
1973	Jan 24
1974	Jan 3
1975	Feb 18
1976	Mar 4
1977	Mar 2
1978	Feb 12
1979	Feb 9
1981	Jan 31
1982	Mar 19
1983	Jan 2
1984	Feb 17
1985	Mar 4
1986	Feb 10
1987	Jan 30
1988	Feb 17
1989	Jan 16
1990	Feb 20
1993	Jan 5
1996	Feb 27
2013	Jan 13
2015	Jan 3

Each year's frost-free daysLong-term trend

See the data as a table

Year	Frost-free days
1894	206
1895	291
1902	260
1903	258
1904	244
1905	279
1906	203
1907	265
1908	259
1909	336
1910	282
1911	263
1912	280
1913	232
1914	330
1915	296
1916	241
1917	262
1918	260
1919	242
1920	250
1921	225
1922	207
1923	268
1924	270
1925	237
1926	319
1927	314
1928	256
1929	217
1930	279
1931	256
1932	223
1933	225
1934	296
1935	219
1936	226
1937	277
1938	227
1939	293
1940	255
1941	319
1942	256
1943	290
1944	241
1945	232
1946	233
1949	204
1950	239
1951	258
1952	245
1953	222
1954	259
1955	224
1956	235
1957	328
1958	257
1959	318
1960	322
1961	338
1962	286
1963	282
1964	249
1965	303
1966	301
1967	351
1968	321
1969	328
1970	270
1971	240
1972	307
1973	340
1974	356
1975	283
1976	269
1977	303
1978	297
1979	321
1980	363
1981	333
1982	272
1983	323
1984	270
1985	253
1986	303
1987	318
1988	312
1989	348
1990	303
1991	363
1993	359
1994	322
1995	363
1996	306
1997	359
1998	339
1999	363
2000	363
2003	359
2013	351
2014	363
2015	358
2016	363

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

See the data as a table

Year	Growing-season temperature
1894	20.3 °C
1895	21.2 °C
1902	19.6 °C
1903	19.8 °C
1904	21.2 °C
1905	19.4 °C
1906	19.8 °C
1907	20.3 °C
1908	20.7 °C
1909	20.8 °C
1910	21.7 °C
1911	20.3 °C
1912	19.6 °C
1913	21.2 °C
1914	20.8 °C
1915	20.6 °C
1916	20.1 °C
1917	21.3 °C
1918	21.3 °C
1919	21.1 °C
1920	20.9 °C
1921	20.9 °C
1922	21.9 °C
1923	20.9 °C
1924	21.5 °C
1925	21.2 °C
1926	22.1 °C
1927	21.2 °C
1928	21.0 °C
1929	21.0 °C
1930	20.4 °C
1931	22.1 °C
1932	20.4 °C
1933	19.6 °C
1934	21.3 °C
1935	20.6 °C
1936	22.0 °C
1937	21.7 °C
1938	21.5 °C
1939	22.1 °C
1940	21.7 °C
1941	20.4 °C
1942	21.0 °C
1943	21.1 °C
1944	20.1 °C
1945	20.7 °C
1946	21.5 °C
1948	20.2 °C
1949	20.8 °C
1950	19.6 °C
1951	20.4 °C
1952	20.8 °C
1953	19.3 °C
1954	21.5 °C
1955	21.3 °C
1956	21.4 °C
1957	21.7 °C
1958	21.7 °C
1959	22.0 °C
1960	22.7 °C
1961	21.6 °C
1962	21.2 °C
1963	20.9 °C
1964	20.7 °C
1965	20.6 °C
1966	22.3 °C
1967	21.6 °C
1968	21.8 °C
1969	22.1 °C
1970	21.9 °C
1971	21.8 °C
1972	22.2 °C
1973	21.4 °C
1974	22.3 °C
1975	21.0 °C
1976	21.7 °C
1977	21.9 °C
1978	22.5 °C
1979	23.1 °C
1980	22.4 °C
1981	23.6 °C
1982	21.9 °C
1983	22.4 °C
1984	24.2 °C
1985	22.6 °C
1986	21.9 °C
1987	23.1 °C
1988	22.9 °C
1989	23.1 °C
1990	23.6 °C
1991	22.1 °C
1993	23.4 °C
1994	23.3 °C
1995	22.8 °C
1996	24.1 °C
1997	24.2 °C
1998	22.5 °C
1999	22.0 °C
2000	24.0 °C
2002	23.2 °C
2003	23.2 °C
2013	23.6 °C
2014	24.2 °C
2015	23.4 °C
2016	23.6 °C

What this means for you: Since 1893, Riverside's last spring frost has come about 4 days earlier per decade, on average. The frost-free season has grown by about 9 days per decade. Year-to-year swings are large, so keep using the safe date rather than the trend.

Source: daily records from Riverside Fire Stn 3 (NOAA GHCN-Daily). Years with too many missing days are left out.

Nearby towns

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