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

The USDA zone info for Alton should be reffered to in order to figure out when it's the best time to 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 a little 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 Alton 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. You can get started a couple of weeks earlier by starting your aubrieta indoors.

Last Frost Date

In Alton the average date of last frost happens on April 15. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Alton may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Alton you get surprised by a frost after April 15 so just be sure to be ready to protect your aubrieta in the event of a late frost.

USDA Zone Info for Alton

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Alton

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