Monitoring the period of frost-free days in your growing area is critical when making spring planting decisions. The frost-free periods listed here indicate the average number of days between the last frost in spring and the first frost each fall.
Use the table below to determine the average number of frost-free days in your area, then consult the crop maturity table to see which crops are best able to grow within that time frame.
Frost-free days across Western Canada, selected locations (numbers refer to last frost first, frost total, frost-free).
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Manitoba
1. Altona May 21 Sept. 18 120
2. Winnipeg May 25 Sept. 22 120
3. The Pas May 27 Sept. 17 113
4. Russell May 28 Sept. 12 107
5. Brandon May 27 Sept. 10 106
6. Thompson June 15 Aug. 16 62
Saskatchewan
7. Maple Creek May 19 Sept. 18 122
8. Moose Jaw May 20 Sept. 18 121
9. Estevan May 21 Sept. 18 120
10. Saskatoon May 21 Sept. 15 117
11. Weyburn May 22 Sept. 12 113
12. Regina May 21 Sept. 10 112
13. Yorkton May 22 Sept. 12 112
14. Prince Albert June 2 Sept. 4 94
15. Choiceland June 7 Sept. 5 90
Alberta
16. Medicine Hat May 16 Sept. 22 129
17. Lethbridge May 17 Sept. 18 124
18. Edmonton May 24 Sept. 23 122
19. Grande Prairie May 18 Sept. 13 118
20. Calgary May 23 Sept. 15 115
21. Olds May 23 Sept. 12 112
22. Red Deer May 25 Sept. 9 107
23. Athabasca June 1 Aug. 29 89
British Columbia
24. Chilliwack April 6 Nov. 9 217
25. Nanaimo April 28 Oct. 17 172
26. Terrace May 5 Oct. 17 165
27. Kelowna May 19 Sept. 20 124
28. Dawson Creek June 5 Aug. 29 116
Dates are calculated based on a 30-year rolling average of the last spring and first fall frosts from station data compiled from 1961 to 1990.
Source: Environment Canada
Average number of days required to reach maturity
Canola, early Polish 73 – 83
Oats 85 – 88
Barley 60 – 90
Buckwheat 80 – 90
Yellow mustard 80 – 90
Brown or Oriental mustard 85 – 95
Wheat 90 – 100
Flax 85 – 100
Field peas 90 – 100
Lentils 85 – 100
Navy beans 90 – 100
Coriander 90 – 100
Canola, late Argentine 92 – 102
Canaryseed 95 – 105
Black beans 95 – 105
Fababeans 105 – 115
Corn 110 – 120
Sunflowers 120 – 130
Sugar beets 120 – 140
Source: Manitoba Agriculture
