One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Dubuque can be used to estimate when it's possible to plant calliopsis.

Planting Calendar for Calliopsis

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

It's not a good idea to plant calliopsis until after the last frost because they do not do well in cold weather.

The earliest that you can plant calliopsis in Dubuque 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 calliopsis and expect a good harvest is probably August. Any later than that and your calliopsis may not have a chance to fully mature. If you are starting your calliopsis indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Dubuque. It might get as low as -20°F during the coldest months of winter.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for Dubuque and it will vary from year to year. Since half of the time in Dubuque it frosts late in the year after April 15 be ready to protect your calliopsis if you have a surprise late frost.

USDA Zone Info for Dubuque

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Dubuque

You may be interested in your other planting guides for Dubuque.