The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You will be able to estimate when you can plant twinspur by referring to the USDA zone info for Ontario.

Planting Calendar for Twinspur

Frost tolerance for twinspur:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since twinspur are moderately cold tolerant you can plant them a bit earlier in the year than other frost tender plants.

The earliest that you can plant twinspur 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 twinspur and expect a good harvest is probably September. If you wait any later than that and your twinspur may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your twinspur indoors.

Last Frost Date

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

Since the USDA zone info for Ontario may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Ontario you get surprised by a frost after April 15 so be sure to be ready to cover your twinspur if you have 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.