One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. 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 steirodiscus in Ontario should be figured out by referring to the USDA zone info.

Planting Calendar for Steirodiscus

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

Steirodiscus tend to make it in a tiny bit of cold which means that you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant steirodiscus 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 steirodiscus and expect a good harvest is probably August. If you wait any later than that and your steirodiscus may not have a chance to really do well. You can get started a couple of weeks earlier by starting your steirodiscus indoors.

Last Frost Date

The average date of last frost is April 15 in Ontario. It might get as low as -15°F during the coldest months of winter.

It's important to remember that USDA zone info for Ontario is an average and the actual date of last frost is different every year. Half of the time in Ontario last frost occurs after April 15 so make sure that you are ready to cover your steirodiscus in the event of one of those late frosts.

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.