One of the best tools that you have as gardeners to help us estimate 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.

It's possible to figure out when it's possible to plant ageratum by using the USDA zone info for Dubuque.

Planting Calendar for Ageratum

Frost tolerance for ageratum:	Not tolerant of frost.
When to plant:	After the last frost.

Since ageratum do not do well in cold weather you have to wait until after the last frost has passed before you can plant them.

The earliest that you can plant ageratum 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 ageratum and expect a good harvest is probably August. You probably don't want to wait any later than that or else your ageratum may not have a chance to really do well. If you are starting your ageratum indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Keep in mind that USDA zone info for Dubuque is an average and the actual date of last frost changes from year to year. Since half of the time in Dubuque it frosts late in the year after April 15 be ready to cover your ageratum in the event of 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.