The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of making a decision about when you can plant digitalis is to refer to the USDA zone info for Ann Arbor.

Planting Calendar for Digitalis

Frost tolerance for digitalis:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Digitalis are one of those plants that can tolerate a little bit of cold weather which means that you can start planting them earlier than other plants that might not handle the cold.

The earliest that you can plant digitalis in Ann Arbor 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 digitalis and expect a good harvest is probably September. Any later than that and your digitalis may not have a chance to grow to maturity. If you are starting your digitalis indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Ann Arbor the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -10°F.

Since the USDA zone info for Ann Arbor is just an average the actual date of last frost will vary from year to year. Half of the time in Ann Arbor you get surprised by a frost after April 15 so be sure to be ready to cover your digitalis in the event of one of those late frosts.

USDA Zone Info for Ann Arbor

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 Ann Arbor

You may be interested in your other planting guides for Ann Arbor.