The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By using the USDA zone info for Ontario it's possible to estimate when it's possible to plant nasturtium.

Planting Calendar for Nasturtium

Frost tolerance for nasturtium:	Not tolerant of frost.
When to plant:	After the last frost.

It's not a good idea to plant nasturtium until after the last frost because they do not do well in cold weather.

The earliest that you can plant nasturtium in Ontario is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant nasturtium and expect a good harvest is probably August. If you wait any later than that and your nasturtium may not have a chance to really do well. You can get started a little bit earlier by starting your nasturtium 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.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Ontario and it changes from year to year. Since half of the time in Ontario last frost occurs after April 15 be ready to cover your nasturtium 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.