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

The USDA zone info for Ontario can be used to figure out when it's the best time to plant arabis.

Planting Calendar for Arabis

Frost tolerance for arabis:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Arabis tend to make it in pretty solid cold which tells us that you can plant them much earlier in the year than more sensitive plants.

The earliest that you can plant arabis in Ontario 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 arabis and expect a good harvest is probably September. Any later than that and your arabis may not have a chance to really do well. Starting your arabis indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Ontario the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -5°F.

Since the USDA zone info for Ontario may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Ontario last frost occurs after April 15 so make sure that you are prepared to protect your arabis if you have a late frost.

USDA Zone Info for Ontario

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Ontario

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