One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of figuring out when it's a good idea to plant scabiosa is to check out the USDA zone info for Ottawa.

Planting Calendar for Scabiosa

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

Since scabiosa do well in moderate cold you can plant them a little earlier in the year than other frost tender plants.

The earliest that you can plant scabiosa 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 scabiosa and expect a good harvest is probably September. Any later than that and your scabiosa may not have a chance to really do well. If you are starting your scabiosa indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Ottawa the average date of last frost happens on April 15. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Ottawa is an average 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 protect your scabiosa 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.