One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. 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 impatiens in Iowa City can be estimated by checking out the USDA zone info.

Planting Calendar for Impatiens

Frost tolerance for impatiens:	Not tolerant of frost.
When to plant:	After the last frost.

Since impatiens are not cold tolerant it is necessary to wait until after the last frost has passed before you can plant them.

The earliest that you can plant impatiens 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 impatiens and expect a good harvest is probably August. Any later than that and your impatiens may not have a chance to really do well. You can get started a couple of weeks earlier by starting your impatiens indoors.

Last Frost Date

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

Remember that USDA zone info for Iowa City may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Iowa City you get a frost after April 15 so be sure to be ready to protect your impatiens 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.