One of the first steps you take when you are getting a good idea 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 Colby can be reffered to in order to figure out when you can plant aubrieta.

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 just a bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant aubrieta in Colby 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 aubrieta and expect a good harvest is probably September. You probably don't want to wait any later than that or else your aubrieta may not have a chance to fully mature. If you are starting your aubrieta indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost is on April 15 in Colby. In the coldest months of winter you should expect an average low temperature of -15°F.

Since the USDA zone info for Colby is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Colby you get a frost after April 15 so make sure that you are ready to protect your aubrieta if you have a late frost.

USDA Zone Info for Colby

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Colby

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