When to plant in Belfast, PE
Planting dates worked out from Belfast's own frost records, not a generic zone chart.
Safe to plant out
May 25
1 year in 10 has a later frost
Average last frost
May 10
about a 50% chance of a later one
Average first fall frost
Oct 29
1 year in 10 by Oct 16
Frost-free days
174
median, 1991–2020
Station used: Alliston · 21.8 km away · station 61 m, town 14 m. How we match towns to stations
This season
Plan your garden.
Planting dates for common crops
| Crop | Start indoors | Plant out or sow | Harvest from |
|---|---|---|---|
| Tomato | Apr 4 – Apr 18 | May 30 – Jun 13 | Jul 24 |
| Sweet pepper | Mar 21 – Apr 4 | May 30 – Jun 13 | Jul 29 |
| Lettuce (leaf) | Mar 22 – Mar 29 | Apr 26 – May 10 | Jun 5 |
| Peas | — | Apr 26 – May 24 | Jun 20 |
| Bush beans | — | May 24 – Jun 14 | Jul 13 |
| Carrot | — | May 7 – Jun 18 | Jul 6 |
| Beet | — | May 7 – Jun 18 | Jun 26 |
| Potato | — | May 7 – May 28 | Jul 16 |
| Kale | Mar 22 – Apr 5 | May 3 – May 17 | Jun 15 |
| Broccoli | Mar 15 – Mar 29 | Apr 26 – May 17 | Jun 25 |
| Cucumber | May 2 – May 9 | May 30 – Jun 13 | Jul 19 |
| Summer squash and zucchini | May 2 – May 9 | May 30 – Jun 13 | Jul 14 |
| Winter squash | May 2 – May 9 | May 30 – Jun 13 | Aug 18 |
| Sweet corn | — | May 24 – Jun 14 | Jul 23 |
| Onion (from sets) | — | Apr 26 – May 17 | Jul 25 |
| Garlic | — | Oct 2 – Oct 30 (fall) | following summer |
| Spinach | — | Apr 26 – May 24 | Jun 3 |
| Basil | Apr 18 – May 2 | May 30 – Jun 13 | Jul 26 |
Belfast'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 |
|---|---|
| 1936 | May 23 |
| 1937 | May 7 |
| 1938 | May 31 |
| 1939 | May 27 |
| 1940 | May 29 |
| 1941 | Jun 6 |
| 1942 | May 7 |
| 1943 | Jun 1 |
| 1944 | May 20 |
| 1945 | Jun 9 |
| 1946 | May 9 |
| 1947 | Jun 8 |
| 1948 | May 17 |
| 1949 | May 25 |
| 1950 | May 22 |
| 1951 | May 18 |
| 1952 | May 18 |
| 1953 | May 27 |
| 1954 | May 14 |
| 1955 | May 2 |
| 1956 | Jun 9 |
| 1957 | May 23 |
| 1958 | May 16 |
| 1959 | Jun 1 |
| 1960 | May 3 |
| 1961 | May 19 |
| 1962 | May 24 |
| 1963 | May 12 |
| 1964 | May 16 |
| 1965 | May 11 |
| 1966 | May 19 |
| 1967 | Jun 2 |
| 1968 | May 28 |
| 1969 | May 27 |
| 1970 | May 26 |
| 1971 | May 1 |
| 1972 | May 26 |
| 1973 | May 8 |
| 1974 | May 31 |
| 1975 | May 18 |
| 1976 | May 16 |
| 1977 | May 19 |
| 1978 | May 24 |
| 1979 | May 13 |
| 1980 | May 25 |
| 1995 | May 26 |
| 1996 | May 9 |
| 1997 | May 25 |
| 1998 | Apr 29 |
| 1999 | Apr 29 |
| 2000 | May 21 |
| 2001 | May 25 |
| 2002 | May 26 |
| 2003 | May 16 |
| 2004 | May 17 |
| 2005 | May 14 |
| 2006 | Apr 30 |
| 2007 | May 24 |
| 2008 | May 4 |
| 2009 | Apr 27 |
| 2010 | Apr 17 |
| 2011 | Apr 22 |
| 2012 | May 3 |
| 2013 | Apr 29 |
| 2014 | May 13 |
| 2015 | May 9 |
| 2016 | May 13 |
Each year's frost-free daysLong-term trend
See the data as a table
| Year | Frost-free days |
|---|---|
| 1936 | 130 |
| 1937 | 149 |
| 1938 | 129 |
| 1939 | 141 |
| 1940 | 140 |
| 1941 | 127 |
| 1942 | 162 |
| 1943 | 131 |
| 1944 | 160 |
| 1945 | 141 |
| 1946 | 164 |
| 1947 | 112 |
| 1948 | 156 |
| 1949 | 149 |
| 1950 | 147 |
| 1951 | 148 |
| 1952 | 153 |
| 1954 | 146 |
| 1955 | 176 |
| 1956 | 109 |
| 1958 | 149 |
| 1959 | 135 |
| 1960 | 163 |
| 1961 | 150 |
| 1962 | 158 |
| 1963 | 150 |
| 1964 | 149 |
| 1965 | 142 |
| 1966 | 160 |
| 1967 | 140 |
| 1968 | 158 |
| 1969 | 145 |
| 1970 | 146 |
| 1971 | 149 |
| 1972 | 131 |
| 1973 | 156 |
| 1974 | 115 |
| 1975 | 144 |
| 1976 | 156 |
| 1977 | 141 |
| 1978 | 132 |
| 1980 | 122 |
| 1995 | 157 |
| 1996 | 158 |
| 1997 | 151 |
| 1998 | 180 |
| 1999 | 173 |
| 2000 | 180 |
| 2001 | 158 |
| 2002 | 157 |
| 2003 | 157 |
| 2004 | 170 |
| 2005 | 181 |
| 2008 | 181 |
| 2009 | 171 |
| 2010 | 196 |
| 2011 | 192 |
| 2012 | 186 |
| 2013 | 183 |
| 2014 | 175 |
| 2015 | 162 |
| 2016 | 176 |
Each year's average temperature, April to SeptemberLong-term trend
See the data as a table
| Year | Growing-season temperature |
|---|---|
| 1936 | 14.0 °C |
| 1937 | 14.7 °C |
| 1938 | 14.3 °C |
| 1939 | 13.2 °C |
| 1940 | 13.2 °C |
| 1941 | 12.4 °C |
| 1942 | 13.9 °C |
| 1944 | 13.8 °C |
| 1945 | 14.0 °C |
| 1946 | 13.4 °C |
| 1947 | 13.5 °C |
| 1948 | 12.8 °C |
| 1949 | 13.7 °C |
| 1950 | 13.2 °C |
| 1951 | 13.8 °C |
| 1952 | 13.8 °C |
| 1954 | 13.1 °C |
| 1955 | 13.2 °C |
| 1956 | 11.4 °C |
| 1957 | 12.2 °C |
| 1958 | 12.6 °C |
| 1959 | 12.9 °C |
| 1960 | 13.2 °C |
| 1961 | 12.9 °C |
| 1962 | 11.8 °C |
| 1963 | 12.0 °C |
| 1964 | 11.6 °C |
| 1965 | 12.0 °C |
| 1966 | 12.4 °C |
| 1967 | 12.4 °C |
| 1968 | 12.9 °C |
| 1969 | 12.6 °C |
| 1970 | 12.9 °C |
| 1971 | 13.4 °C |
| 1972 | 12.7 °C |
| 1973 | 13.4 °C |
| 1974 | 12.6 °C |
| 1975 | 13.3 °C |
| 1976 | 14.0 °C |
| 1977 | 12.8 °C |
| 1978 | 12.7 °C |
| 1980 | 12.3 °C |
| 1981 | 12.8 °C |
| 1995 | 12.3 °C |
| 1996 | 13.4 °C |
| 1997 | 12.7 °C |
| 1998 | 14.2 °C |
| 1999 | 15.5 °C |
| 2000 | 13.3 °C |
| 2001 | 14.2 °C |
| 2002 | 13.6 °C |
| 2003 | 14.1 °C |
| 2004 | 13.5 °C |
| 2005 | 14.0 °C |
| 2006 | 14.7 °C |
| 2007 | 13.1 °C |
| 2008 | 14.2 °C |
| 2009 | 14.3 °C |
| 2010 | 15.0 °C |
| 2011 | 14.1 °C |
| 2012 | 15.4 °C |
| 2013 | 14.7 °C |
| 2014 | 14.2 °C |
| 2015 | 13.9 °C |
| 2016 | 13.9 °C |
What this means for you: Since 1936, Belfast'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 Alliston (NOAA GHCN-Daily, from Environment and Climate Change Canada). Years with too many missing days are left out.