One of the first steps you take when you are estimating 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.

You can figure out when it's the best time to plant hardy hibiscus in Ontario by referring to the USDA zone info.

Planting Calendar for Hardy Hibiscus

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

Hardy Hibiscus are very cold tolerant which tells us that you can get them planted much earlier than plants that are more sensitive to the cold.

The earliest that you can plant hardy hibiscus in Ontario is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant hardy hibiscus and expect a good harvest is probably October. If you wait any later than that and your hardy hibiscus may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your hardy hibiscus indoors.

Last Frost Date

In Ontario the average date of last frost happens on January 31. You can expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for Ontario is not always accurate the actual date of last frost changes from year to year. Half of the time in Ontario there is a last frost after January 31 so make sure that you are prepared to protect your hardy hibiscus in the event of a surprise late frost.

USDA Zone Info for Ontario

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Ontario

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