One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of determining when it's the best time to plant borage is to refer to the USDA zone info for Ontario.

Planting Calendar for Borage

Frost tolerance for borage:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant borage a little bit earlier in the year because they do well in moderate cold.

The earliest that you can plant borage in Ontario is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant borage and expect a good harvest is probably October. Any later than that and your borage may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your borage indoors.

Last Frost Date

In Ontario the average date of last frost happens on January 31. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for Ontario is just an average the actual date of last frost will vary from year to year. Since half of the time in Ontario it frosts late in the year after January 31 be ready to cover your borage if you have one of those late frosts.

USDA Zone Info for Ontario

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Ontario

You may be interested in your other planting guides for Ontario.