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

The USDA zone info for Iowa City can be used to figure out when you can plant rudbeckia.

Planting Calendar for Rudbeckia

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

Since rudbeckia are one of those plants that can tolerate a little bit of cold weather you can plant them a little earlier in the year than more sensitive plants.

The earliest that you can plant rudbeckia 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 rudbeckia and expect a good harvest is probably September. You probably don't want to wait any later than that or else your rudbeckia may not have a chance to grow to maturity. You can get started a little bit earlier by starting your rudbeckia indoors.

Last Frost Date

The average date of last frost is April 15 in Iowa City. 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. Half of the time in Iowa City it frosts late in the year after April 15 so just be sure to be ready to protect your rudbeckia 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.