Frost Dates Explained

In No Guff Vegetable Gardening we tell readers that frost is more than just ice crystals on the window: it’s something we use for planning the vegetable garden.


Here’s what we say in the book No Guff Vegetable Gardening about frost dates:


Frost matters to vegetable gardeners. But more than a destructive force, gardeners use knowledge of frost for planning:

  • Average frost dates are useful when planning a vegetable garden.The average last spring frost date is important for vegetable gardeners because it is the milepost that helps us decide when to plant seeds indoors and in the garden.
  • The date of the average first fall frost is important too: More than the curtain falling at the end of the summer show, it allows us to gauge how many frost-free growing days we have—something that is important to know when choosing crop varieties. Some tomato varieties, for example, are ready in 60 days, while others take 85 days. The difference of 25 days is a big deal in an area with a short frost-free period.

Don’t restrict yourself to published first- and last-frost dates. Talk to other gardeners in the area to find out what dates they use—because your microclimate might be unique.


Coming soon: average frost dates for towns and cities across Canada.

Steve says: I bet you go for the fastest maturing tomatoes there in Calgary, Donna!

Donna says: I know you live in the banana belt—in Toronto—Steve.