Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant aubrieta in Havre should be figured out by reviewing the USDA zone info.

Planting Calendar for Aubrieta

Frost tolerance for aubrieta:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Aubrieta can survive in some cold which tells us that you can plant them a little bit earlier in the year than other frost tender plants.

The earliest that you can plant aubrieta 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 aubrieta and expect a good harvest is probably August. You probably don't want to wait any later than that or else your aubrieta may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your aubrieta indoors.

Last Frost Date

On average the last frost has passed is on May 15 in Havre. You can expect an average low temperature of -30°F in the coldest months of winter.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Havre and it changes from year to year. Half of the time in Havre you get a frost after May 15 so make sure that you are ready to protect your aubrieta in the event of a late frost.

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.