Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of estimating when to plant impatiens is to look at the USDA zone info for Ottawa.

Planting Calendar for Impatiens

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

Since impatiens are not cold tolerant it is important to wait until after the last frost before you can plant them.

The earliest that you can plant impatiens 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 impatiens and expect a good harvest is probably August. You probably don't want to wait any later than that or else your impatiens may not have a chance to grow to maturity. You can get started a little bit earlier by starting your impatiens indoors.

Last Frost Date

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

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Ottawa and it is different every year. Since half of the time in Ottawa it frosts late in the year after April 15 be ready to protect your impatiens if you have a surprise 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.