One of the best tools that you have as gardeners to help us determine 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.

In Ottawa you can figure out when it's the best time to plant bittercress by using the USDA zone info.

Planting Calendar for Bittercress

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

You can plant bittercress slightly earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

The earliest that you can plant bittercress in Ottawa 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 bittercress and expect a good harvest is probably August. If you wait any later than that and your bittercress may not have a chance to fully mature. You can get started a few weeks earlier by starting your bittercress indoors.

Last Frost Date

On average the last frost is on April 15 in Ottawa. In the coldest months of winter you should expect an average low temperature of -10°F.

Since the USDA zone info for Ottawa is just an average the actual date of last frost will vary from year to year. Half of the time in Ottawa it frosts late in the year after April 15 so just be sure to be ready to protect your bittercress in the event of one of those late frosts.

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.