One of the first steps you take when you are making a decision about your gardening schedule is find your 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 reffered to in order to estimate when it's possible to plant campanula.

Planting Calendar for Campanula

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

Campanula do well in moderate cold which means that you can plant them a little bit earlier in the year than other plants that might not handle the cold.

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

Last Frost Date

The average date of last frost is January 31 in Ontario. You can expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for Ontario is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Ontario you get surprised by a frost after January 31 so just be sure to be ready to cover your campanula in the event of a late frost.

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.