One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can determine when it's a good idea to plant nemesia in Ottawa by referring to the USDA zone info.

Planting Calendar for Nemesia

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

Since nemesia require warm weather it's necessary to wait until after the last frost has passed before you can plant them.

The earliest that you can plant nemesia 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 nemesia and expect a good harvest is probably August. Any later than that and your nemesia may not have a chance to really do well. You can get started a few weeks earlier by starting your nemesia indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Ottawa. It might get as low as -15°F during the coldest months of winter.

It's important to remember that USDA zone info for Ottawa is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Ottawa there is a last frost after April 15 be ready to cover your nemesia in the event of a surprise late frost.

USDA Zone Info for Ottawa

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Ottawa

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