Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You should be able to estimate when it's a good idea to plant anchusa by reviewing the USDA zone info for Iowa City.

Planting Calendar for Anchusa

Frost tolerance for anchusa:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

You can plant anchusa earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

The earliest that you can plant anchusa 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 anchusa and expect a good harvest is probably September. You probably don't want to wait any later than that or else your anchusa may not have a chance to really do well. Starting your anchusa indoors is a great way to get them started a little bit earlier.

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 is just an average the actual date of last frost will vary from year to year. Since half of the time in Iowa City you get surprised by a frost after April 15 be ready to protect your anchusa if you have 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.