Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant iresene in Ottawa can be determined by reviewing the USDA zone info.

Planting Calendar for Iresene

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

Iresene do not do well in cold weather which means that you have to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

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

Last Frost Date

The average date of last frost is April 15 in Ottawa. You should expect an average low temperature of -10°F in the coldest months of winter.

Keep in mind that USDA zone info for Ottawa is just an average and the actual date of last frost changes from year to year. Since half of the time in Ottawa you get a frost after April 15 be ready to protect your iresene if you have a late frost.

USDA Zone Info for Ottawa

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Ottawa

You may be interested in your other planting guides for Ottawa.