One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of making a decision about when it's a good idea to plant ajuga is to look at the USDA zone info for Ontario.

Planting Calendar for Ajuga

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

Ajuga tend to make it in quite a bit of cold which tells us that you can plant them quite a bit earlier in the year than more sensitive plants.

The earliest that you can plant ajuga 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 ajuga and expect a good harvest is probably September. Any later than that and your ajuga may not have a chance to grow to maturity. If you are starting your ajuga indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Ontario. It might get as low as -5°F during the coldest months of winter.

It's important to remember that USDA zone info for Ontario is not always accurate and the actual date of last frost will vary from year to year. Since half of the time in Ontario you get surprised by a frost after April 15 be ready to protect your ajuga in the event of one of those late frosts.

USDA Zone Info for Ontario

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Ontario

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