One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when it's a good idea to plant aubrieta in Zone 3a by using 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.

You can plant aubrieta a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant aubrieta in Zone 3a 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. If you wait any later than that and your aubrieta may not have a chance to really do well. Starting your aubrieta indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on May 15 in Zone 3a. It might get as low as -40°F during the coldest months of winter.

Since the USDA zone info for Zone 3a is not always accurate the actual date of last frost is different every year. Half of the time in Zone 3a it frosts late in the year after May 15 so just be sure to be ready to cover your aubrieta in the event of a late frost.

USDA Zone Info for Zone 3a

Here is the info for USDA Zone 3a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-40°F
Highest Expected Low	-35°F

This means that on a really cold year, the coldest it will get is -40°F. On most years you should be prepared to experience lows near -35°F.

Plants to Grow in Zone 3a

You may be interested in your other planting guides for Zone 3a.