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

By referring to the USDA zone info for Williston it's a good idea to determine when it's the best time to plant foxglove.

Planting Calendar for Foxglove

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

Since foxglove are moderately cold tolerant you can plant them a little bit earlier in the year than more sensitive plants.

The earliest that you can plant foxglove in Williston 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. Any later than that and your foxglove may not have a chance to grow to maturity. If you are starting your foxglove indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Williston the average date of last frost happens on May 15. It might get as low as -30°F during the coldest months of winter.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Williston and it is different every year. Half of the time in Williston there is a last frost after May 15 so make sure that you are prepared to cover your foxglove if you have one of those late frosts.

USDA Zone Info for Williston

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Williston

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