One of the first steps you take when you are making a decision about 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.

The USDA zone info for Havre should be read to figure out when it's possible to plant aubretia.

Planting Calendar for Aubretia

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

Since aubretia do well in cold you can plant them quite a bit earlier in the year than more sensitive plants.

The earliest that you can plant aubretia in Havre 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 aubretia and expect a good harvest is probably August. You probably don't want to wait any later than that or else your aubretia may not have a chance to grow to maturity. Starting your aubretia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Havre. You should expect an average low temperature of -30°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Havre is not always accurate and the actual date of last frost changes from year to year. Half of the time in Havre you get surprised by a frost after May 15 so make sure that you are prepared to cover your aubretia in the event of one of those late frosts.

USDA Zone Info for Havre

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Havre

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