The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant peonies in Ontario should be estimated by reviewing the USDA zone info.

Planting Calendar for Peonies

Frost tolerance for peonies:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant peonies slightly earlier in the year because they do ok in moderate cold.

The earliest that you can plant peonies 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 peonies and expect a good harvest is probably September. You probably don't want to wait any later than that or else your peonies may not have a chance to grow to maturity. If you are starting your peonies 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 January 31 in Ontario. It might get as low as 30°F during the coldest months of winter.

It's important to remember that USDA zone info for Ontario may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in Ontario there is a last frost after January 31 so just be sure to be ready to cover your peonies if you have a surprise 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.