One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of making a decision about when it's the best time to plant potatos is to use the USDA zone info for Ontario.

Planting Calendar for Potatos

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

You can plant potatos a lot earlier in the year because they do well in cold.

The earliest that you can plant potatos 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 potatos and expect a good harvest is probably September. You probably don't want to wait any later than that or else your potatos may not have a chance to fully mature. You can get started a few weeks earlier by starting your potatos indoors.

Last Frost Date

The average date of last frost is April 15 in Ontario. In the coldest months of winter you should expect an average low temperature of -5°F.

Just be sure to remember that USDA zone info for Ontario is not always accurate and the actual date of last frost is different every year. Half of the time in Ontario last frost occurs after April 15 so make sure that you are prepared to protect your potatos 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.