Planting 101: First and Last Frost, Number of Frost Free Days

To determine when, what, and where to plant you will need to start with knowing the approximate last and first frosts of the season.

If you live in Alberta, Saskatchewan, or Manitoba this is a good resource:

Choose your city, or the one closest to you, and it will give you all the frosty information you need.

City of Origin

Average number of frost-free days 120
Average date of last spring frost May 21
Number of years last spring frost fell
Before May 31 16
Between June 1 – 15 3
After June 15 0
Average date of first fall frost September 18
Number of years first frost fell
Before August 31 2
Between September 1 – 15 5
After September 15 12

If you live outside the prairie provinces there are many other charts. Google is your friend. Search: Number of frost free days (city name) and you should find a chart that suits your needs.