The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You will be able to estimate when it's a good idea to plant aubretia by reviewing the USDA zone info for Ottawa.

Planting Calendar for Aubretia

Frost tolerance for aubretia:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Aubretia tend to make it in pretty solid cold which tells us that you can plant them earlier in the year than more sensitive plants.

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

The last month that you can plant aubretia and expect a good harvest is probably September. If you wait any later than that and your aubretia may not have a chance to grow to maturity. If you are starting your aubretia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Ottawa. In the coldest months of winter you should expect an average low temperature of -15°F.

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 will vary from year to year. Half of the time in Ottawa there is a last frost after April 15 so just be sure to be ready to protect your aubretia 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.