One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of making a decision about when it's a good idea to plant verbena is to check out the USDA zone info for Madison.

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.

Since verbena are one of those plants that can tolerate a tiny bit of cold weather you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant verbena in Madison 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. If you are starting your verbena indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

It's important to remember that USDA zone info for Madison is an average and the actual date of last frost will vary from year to year. Since half of the time in Madison there is a last frost after May 15 be ready to cover your verbena in the event of a late frost.

USDA Zone Info for Madison

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 Madison

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