The USDA Zone info is a great tool for gardeners to help us figure out 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.

The USDA zone info for Ontario should be read to determine when to plant argyranthemum.

Planting Calendar for Argyranthemum

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

Since argyranthemum require warm weather you need to wait until after the last frost before you can plant them.

The earliest that you can plant argyranthemum 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 argyranthemum and expect a good harvest is probably September. 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 little bit earlier.

Last Frost Date

On average the last frost has passed is on January 31 in Ontario. In the coldest months of winter you can expect an average low temperature of 30°F.

Just be sure to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Ontario and it changes from year to year. Half of the time in Ontario you get a frost after January 31 so just be sure to be ready to cover your argyranthemum if you have 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.