The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Ottawa you can determine when it's a good idea to plant xerianthemum by referring to the USDA zone info.

Planting Calendar for Xerianthemum

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

You can plant xerianthemum slightly earlier in the year because they do ok in moderate cold.

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

Last Frost Date

The average date of last frost is 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 not always accurate the actual date of last frost is different every year. Since half of the time in Ottawa there is a last frost after April 15 be ready to cover your xerianthemum in the event of a surprise 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.