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 determine when you can plant crassula by looking at the USDA zone info.

Planting Calendar for Crassula

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

Since crassula are not cold tolerant you must wait until after the last frost before you can plant them.

The earliest that you can plant crassula 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 crassula and expect a good harvest is probably August. If you wait any later than that and your crassula may not have a chance to really do well. You can get started a couple of weeks earlier by starting your crassula indoors.

Last Frost Date

On average the last frost is on April 15 in Ottawa. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Ottawa is an average the actual date of last frost changes from year to year. Since half of the time in Ottawa you get a frost after April 15 be ready to cover your crassula in the event of one of those late frosts.

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.