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

A way of getting a good idea when it's a good idea to plant verbena is to use the USDA zone info for Holmen.

Planting Calendar for Verbena

Frost tolerance for verbena:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

You can plant verbena slightly earlier in the year because they do ok in moderate cold.

The earliest that you can plant verbena in Holmen is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant verbena and expect a good harvest is probably August. If you wait any later than that and your verbena may not have a chance to fully mature. You can get started a little bit earlier by starting your verbena indoors.

Last Frost Date

On average all chance of frost has passed is on May 15 in Holmen. In the coldest months of winter you can expect an average low temperature of -25°F.

Since the USDA zone info for Holmen is an average the actual date of last frost will vary from year to year. Since half of the time in Holmen last frost occurs after May 15 be ready to cover your verbena if you have a surprise late frost.

USDA Zone Info for Holmen

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 Holmen

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