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.

You will be able to determine when it's the best time to plant pumpkins by checking out the USDA zone info for Iowa City.

Planting Calendar for Pumpkins

Frost tolerance for pumpkins:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Pumpkins are not cold tolerant which means that it is important to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant pumpkins 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 pumpkins and expect a good harvest is probably August. You probably don't want to wait any later than that or else your pumpkins may not have a chance to really do well. You can get started a couple of weeks earlier by starting your pumpkins indoors.

Last Frost Date

The average date of last frost is April 15 in Iowa City. In the coldest months of winter you should 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 will vary from year to year. Half of the time in Iowa City it frosts late in the year after April 15 so make sure that you are prepared to cover your pumpkins if you have 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.