One of the first steps you take when you are figuring out your gardening schedule is find your 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.

The first opportunity to plant dipladenia in Ottawa should be estimated by reviewing the USDA zone info.

Planting Calendar for Dipladenia

Frost tolerance for dipladenia:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

It's probably a bad idea to plant dipladenia until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant dipladenia 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 dipladenia and expect a good harvest is probably August. You probably don't want to wait any later than that or else your dipladenia may not have a chance to fully mature. Starting your dipladenia indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Ottawa. In the coldest months of winter you can expect an average low temperature of -10°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 Ottawa and it can change quite a bit from year to year. Half of the time in Ottawa last frost occurs after April 15 so always be ready to cover your dipladenia 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.