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

A common way of estimating when it's possible to plant anchusa is to check out the USDA zone info for Viroqua.

Planting Calendar for Anchusa

Frost tolerance for anchusa:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Anchusa do ok in pretty solid cold which means that you can plant them earlier in the year than other plants that might not handle the cold.

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

Last Frost Date

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

Since the USDA zone info for Viroqua is just an average the actual date of last frost is different every year. Half of the time in Viroqua you get surprised by a frost after May 15 so make sure that you are ready to protect your anchusa in the event of a late frost.

USDA Zone Info for Viroqua

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 Viroqua

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