One of the best tools that you have as gardeners to help us estimate 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.

In Zone 4a you can determine when it's possible to plant aubretia by checking out the USDA zone info.

Planting Calendar for Aubretia

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

You can plant aubretia a lot earlier in the year because they do well in cold.

The earliest that you can plant aubretia in Zone 4a 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. Any later than that and your aubretia may not have a chance to really do well. Starting your aubretia indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost is on May 15 in Zone 4a. It might get as low as -30°F during the coldest months of winter.

Since the USDA zone info for Zone 4a is an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Zone 4a you get surprised by a frost after May 15 be ready to protect your aubretia in the event of one of those late frosts.

USDA Zone Info for Zone 4a

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 Zone 4a

You may be interested in your other planting guides for Zone 4a.