One of the best tools that you have as gardeners to help us determine 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 estimate when it's possible to plant perilla.

Planting Calendar for Perilla

Frost tolerance for perilla:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Perilla require warm weather which means that you must wait until it warms up after the last frost before you can plant them.

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

Last Frost Date

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

Always keep in mind 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. Half of the time in Ontario there is a last frost after January 31 so always be ready to protect your perilla if you have 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.