The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By looking at the USDA zone info for Ottawa it's possible to figure out when you can plant sweet woodruff.

Planting Calendar for Sweet Woodruff

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

Sweet Woodruff are moderately cold tolerant which tells us that you can plant them earlier than other frost tender plants.

The earliest that you can plant sweet woodruff 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 sweet woodruff and expect a good harvest is probably September. If you wait any later than that and your sweet woodruff may not have a chance to fully mature. If you are starting your sweet woodruff indoors then you might be able to get away with starting them a little bit earlier.

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 an average and the actual date of last frost is different every year. Half of the time in Ottawa there is a last frost after April 15 so be sure to be ready to cover your sweet woodruff in the event of 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.