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.

You can estimate when it's possible to plant scallions in Ontario by checking out the USDA zone info.

Planting Calendar for Scallions

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

Scallions are barely cold tolerant which tells us that you can start planting them slightly earlier than more sensitive plants.

The earliest that you can plant scallions 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 scallions and expect a good harvest is probably September. You probably don't want to wait any later than that or else your scallions may not have a chance to grow to maturity. Starting your scallions indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Ontario the average date of last frost happens on January 31. You should expect an average low temperature of 30°F in the coldest months of winter.

Just be sure to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Ontario and it is different every year. Since half of the time in Ontario you get surprised by a frost after January 31 be ready to protect your scallions 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.