One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of figuring out when it's a good idea to plant aubretia is to consult the USDA zone info for Sterling.

Planting Calendar for Aubretia

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

Aubretia do well in pretty solid cold which means that you can plant them a lot earlier in the year than other frost tender plants.

The earliest that you can plant aubretia in Sterling 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. 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 couple of weeks earlier.

Last Frost Date

In Sterling the average date of last frost happens on April 15. You should expect an average low temperature of -20°F in the coldest months of winter.

Always keep in mind that USDA zone info for Sterling is an average and the actual date of last frost is different every year. Since half of the time in Sterling you get a frost after April 15 be ready to cover your aubretia in the event of a surprise late frost.

USDA Zone Info for Sterling

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Sterling

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