The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Iowa City you can figure out when you can plant dipladenia by using the USDA zone info.

Planting Calendar for Dipladenia

Frost tolerance for dipladenia:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Since dipladenia require warm weather you must wait until after the last frost has passed before you can plant them.

The earliest that you can plant dipladenia in Iowa City 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 dipladenia and expect a good harvest is probably August. Any later than that and your dipladenia may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your dipladenia indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Iowa City. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Iowa City may not be accurate from year to year the actual date of last frost will vary from year to year. Half of the time in Iowa City you get surprised by a frost after April 15 so be sure to be ready to cover your dipladenia in the event of a 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.