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

A common way of determining when you can plant argyranthemum is to examine the USDA zone info for Ontario.

Planting Calendar for Argyranthemum

Frost tolerance for argyranthemum:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since argyranthemum are not cold tolerant it's necessary to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant argyranthemum 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 argyranthemum and expect a good harvest is probably August. If you wait any later than that and your argyranthemum may not have a chance to fully mature. If you are starting your argyranthemum indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Ontario. 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 will vary from year to year. Since half of the time in Ontario you get surprised by a frost after April 15 be ready to protect your argyranthemum in the event of one of those late frosts.

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.