One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By checking out the USDA zone info for Winterset you should be able to determine when it's a good idea to plant verbena.

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 barely cold tolerant you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant verbena in Winterset 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 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 really do well. If you are starting your verbena indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Winterset the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -20°F.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Winterset and it will vary from year to year. Since half of the time in Winterset you get a frost after April 15 be ready to protect your verbena if you have a late frost.

USDA Zone Info for Winterset

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Winterset

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