Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant aubretia in Ontario should be figured out by reviewing the USDA zone info.

Planting Calendar for Aubretia

Frost tolerance for aubretia:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Aubretia are very cold tolerant which tells us that you can start planting them much earlier than more sensitive plants.

The earliest that you can plant aubretia 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 aubretia and expect a good harvest is probably September. Any later than that and your aubretia may not have a chance to fully mature. Starting your aubretia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Ontario the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Ontario is just an average the actual date of last frost will vary from year to year. Half of the time in Ontario it frosts late in the year after April 15 so make sure that you are prepared to protect your aubretia if you have 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.