One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Ontario you can estimate when it's the best time to plant asparagus fern by referring to the USDA zone info.

Planting Calendar for Asparagus Fern

Frost tolerance for asparagus fern:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Asparagus Fern are not cold tolerant which tells us that you need to wait until it warms up after all chance of frost has passed before you can plant them.

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

Last Frost Date

The average date of last frost is January 31 in Ontario. It might get as low as 30°F during the coldest months of winter.

Keep in mind that USDA zone info for Ontario is an average and the actual date of last frost will vary from year to year. Since half of the time in Ontario it frosts late in the year after January 31 be ready to cover your asparagus fern in the event of a 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.