Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Superior you can determine when to plant foxglove by using the USDA zone info.

Planting Calendar for Foxglove

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

You can plant foxglove 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 foxglove in Superior 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 foxglove and expect a good harvest is probably August. You probably don't want to wait any later than that or else your foxglove may not have a chance to really do well. Starting your foxglove indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Superior the average date of last frost happens on May 15. You should expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Superior is not always accurate the actual date of last frost changes from year to year. Half of the time in Superior there is a last frost after May 15 so always be ready to cover your foxglove in the event of a late frost.

USDA Zone Info for Superior

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Superior

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