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.

In Ottawa you can figure out when to plant regal geranium by checking out the USDA zone info.

Planting Calendar for Regal Geranium

Frost tolerance for regal geranium:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Regal Geranium do ok in moderate cold which tells us that you can start planting them slightly earlier than other frost tender plants.

The earliest that you can plant regal geranium in Ottawa is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant regal geranium and expect a good harvest is probably August. Any later than that and your regal geranium may not have a chance to really do well. If you are starting your regal geranium indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Ottawa is just an average the actual date of last frost changes from year to year. Half of the time in Ottawa you get surprised by a frost after April 15 so make sure that you are prepared to protect your regal geranium in the event of 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.