Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to estimate when to plant xerianthemum by referring to the USDA zone info for Ontario.

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.

Xerianthemum do ok in moderate cold which tells us that you can plant them slightly earlier than other plants that might not handle the cold.

The earliest that you can plant xerianthemum in Ontario 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. If you wait any later than that and your xerianthemum may not have a chance to fully mature. Starting your xerianthemum indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Ontario. You should expect an average low temperature of -15°F in the coldest months of winter.

Keep in mind that USDA zone info for Ontario is not always accurate and the actual date of last frost is different every year. Half of the time in Ontario last frost occurs after April 15 so be sure to be ready to protect your xerianthemum in the event of a late frost.

USDA Zone Info for Ontario

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 Ontario

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