Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In De Pere you can determine when it's possible to plant cardinal flower by reviewing the USDA zone info.

Planting Calendar for Cardinal Flower

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

Since cardinal flower are not cold tolerant you have to wait until after the last frost before you can plant them.

The earliest that you can plant cardinal flower 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 cardinal flower and expect a good harvest is probably August. You probably don't want to wait any later than that or else your cardinal flower may not have a chance to grow to maturity. You can get started a little bit earlier by starting your cardinal flower indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in De Pere. In the coldest months of winter you should expect an average low temperature of -20°F.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for De Pere and it can change quite a bit from year to year. Since half of the time in De Pere there is a last frost after April 15 be ready to protect your cardinal flower in the event of a late frost.

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.