The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to determine when it's the best time to plant geranium by reviewing the USDA zone info for Ottawa.

Planting Calendar for Geranium

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

Since geranium are not cold tolerant you have to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant geranium 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 geranium and expect a good harvest is probably August. If you wait any later than that and your geranium may not have a chance to grow to maturity. If you are starting your geranium indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Ottawa. It might get as low as -10°F during the coldest months of winter.

Keep in mind that USDA zone info for Ottawa is an average and the actual date of last frost will vary from year to year. Half of the time in Ottawa last frost occurs after April 15 so make sure that you are ready to cover your geranium in the event of one of those late frosts.

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.