One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Ontario you can estimate when to plant aubrieta by looking at the USDA zone info.

Planting Calendar for Aubrieta

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

Since aubrieta are moderately cold tolerant you can plant them a little bit earlier in the year than more sensitive plants.

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

The last month that you can plant aubrieta and expect a good harvest is probably September. Any later than that and your aubrieta may not have a chance to really do well. You can get started a little bit earlier by starting your aubrieta indoors.

Last Frost Date

The average date of last frost is April 15 in Ontario. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Ontario is not always accurate the actual date of last frost can change quite a bit from year to year. Since half of the time in Ontario you get a frost after April 15 be ready to cover your aubrieta in the event of a late frost.

USDA Zone Info for Ontario

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Ontario

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