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 you can plant balloon flower by referring to the USDA zone info for Dubuque.

Planting Calendar for Balloon Flower

Frost tolerance for balloon flower:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Balloon Flower do ok in moderate cold which tells us that you can get them planted just a bit earlier than other plants that might not handle the cold.

The earliest that you can plant balloon flower in Dubuque is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant balloon flower and expect a good harvest is probably August. Any later than that and your balloon flower may not have a chance to fully mature. Starting your balloon flower indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Dubuque the average date of last frost happens on April 15. You should expect an average low temperature of -20°F in the coldest months of winter.

Since the USDA zone info for Dubuque is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Dubuque it frosts late in the year after April 15 so always be ready to cover your balloon flower if you have one of those late frosts.

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.