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.

By checking out the USDA zone info for Ottawa it's possible to estimate when you can plant kale.

Planting Calendar for Kale

Frost tolerance for kale:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Kale do ok in a little bit of cold which tells us that you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant kale in Ottawa 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 kale and expect a good harvest is probably September. You probably don't want to wait any later than that or else your kale may not have a chance to grow to maturity. Starting your kale 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 Ottawa. It might get as low as -10°F during the coldest months of winter.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Ottawa and it changes from year to year. Half of the time in Ottawa you get a frost after April 15 so always be ready to protect your kale if you have a late frost.

USDA Zone Info for Ottawa

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Ottawa

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