The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of getting a good idea when to plant twinspur is to look at the USDA zone info for Iowa City.

Planting Calendar for Twinspur

Frost tolerance for twinspur:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Twinspur do well in moderate cold which means that you can plant them a little bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant twinspur in Iowa City is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant twinspur and expect a good harvest is probably September. You probably don't want to wait any later than that or else your twinspur may not have a chance to fully mature. You can get started a few weeks earlier by starting your twinspur indoors.

Last Frost Date

In Iowa City the average date of last frost happens on April 15. It might get as low as -15°F during 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 is different every year. Since half of the time in Iowa City there is a last frost after April 15 be ready to protect your twinspur in the event of one of those late frosts.

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.