Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant verbena in Iowa City should be estimated by referring to the USDA zone info.

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.

Verbena do ok in some cold which means that you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant verbena in Iowa City 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. You probably don't want to wait any later than that or else 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 few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Iowa City. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Iowa City is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Iowa City last frost occurs after April 15 so always be ready to cover your verbena in the event of a surprise late frost.

USDA Zone Info for Iowa City

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Iowa City

You may be interested in your other planting guides for Iowa City.