The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Toronto should be read to figure out when it's possible to plant lemon balm.

Planting Calendar for Lemon balm

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

Lemon balm do ok in moderate cold which means that you can plant them slightly earlier than more sensitive plants.

The earliest that you can plant lemon balm in Toronto is March. However, you really should wait until April if you don't want to take any chances.

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

Last Frost Date

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

Since the USDA zone info for Toronto is just an average the actual date of last frost will vary from year to year. Since half of the time in Toronto there is a last frost after April 15 be ready to cover your lemon balm in the event of a late frost.

USDA Zone Info for Toronto

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 Toronto

You may be interested in your other planting guides for Toronto.