One of the first steps you take when you are figuring out your gardening schedule is find your 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 best time to plant cardinal flower in Willowbrook should be determined 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 do not do well in cold weather it's important to wait until after the last frost has passed before you can plant them.

The earliest that you can plant cardinal flower in Willowbrook 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 really do well. Starting your cardinal flower indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Willowbrook. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Willowbrook is not always accurate the actual date of last frost changes from year to year. Half of the time in Willowbrook you get surprised by a frost after April 15 so just be sure to be ready to cover your cardinal flower in the event of a late frost.

USDA Zone Info for Willowbrook

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Willowbrook

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