The USDA Zone info is a great tool for gardeners to help us estimate 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.

The first chance to plant strawflowers in Ottawa can be determined by reviewing the USDA zone info.

Planting Calendar for Strawflowers

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

Strawflowers tend to make it in a tiny bit of cold which tells us that you can plant them slightly earlier in the year than more sensitive plants.

The earliest that you can plant strawflowers 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 strawflowers and expect a good harvest is probably August. You probably don't want to wait any later than that or else your strawflowers may not have a chance to fully mature. If you are starting your strawflowers indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Ottawa. You should expect an average low temperature of -15°F in the coldest months of winter.

Just be sure to 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 there is a last frost after April 15 so be sure to be ready to cover your strawflowers if you have a late frost.

USDA Zone Info for Ottawa

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Ottawa

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