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.

The USDA zone info for Ontario should be used to figure out when to plant thyme.

Planting Calendar for Thyme

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

Since thyme do well in cold you can plant them earlier in the year than other frost tender plants.

The earliest that you can plant thyme 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 thyme and expect a good harvest is probably September. Any later than that and your thyme may not have a chance to grow to maturity. Starting your thyme indoors is a great way to get them started a little bit 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 -5°F.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Ontario and it changes from year to year. Half of the time in Ontario last frost occurs after April 15 so just be sure to be ready to cover your thyme if you have 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.