One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to determine when to plant calliopsis by referring to the USDA zone info for De Pere.

Planting Calendar for Calliopsis

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

Since calliopsis are not cold tolerant you must wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant calliopsis in De Pere 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. You probably don't want to wait any later than that or else 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 few weeks earlier.

Last Frost Date

In De Pere the average date of last frost happens on April 15. It might get as low as -20°F during the coldest months of winter.

Remember that USDA zone info for De Pere is just an average and the actual date of last frost changes from year to year. Since half of the time in De Pere last frost occurs after April 15 be ready to protect your calliopsis in the event of one of those late frosts.

USDA Zone Info for De Pere

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 De Pere

You may be interested in your other planting guides for De Pere.