Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant bishop's weed in Ottawa can be determined by referring to the USDA zone info.

Planting Calendar for Bishop's Weed

Frost tolerance for bishop's weed:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

You can plant bishop's weed a lot earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

The earliest that you can plant bishop's weed 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 bishop's weed and expect a good harvest is probably September. If you wait any later than that and your bishop's weed may not have a chance to grow to maturity. You can get started a little bit earlier by starting your bishop's weed indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Ottawa. It might get as low as -10°F during the coldest months of winter.

Remember that USDA zone info for Ottawa is just an average and the actual date of last frost will vary from year to year. Since half of the time in Ottawa you get surprised by a frost after April 15 be ready to cover your bishop's weed if you have 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.