The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant cardinal flower in Lisle should be estimated 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 when the weather gets warmer.

It's probably not a good idea to plant cardinal flower until after the last frost because they are not cold tolerant.

The earliest that you can plant cardinal flower in Lisle 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. Any later than that and your cardinal flower may not have a chance to fully mature. You can get started a few weeks earlier by starting your cardinal flower indoors.

Last Frost Date

The average date of last frost is April 15 in Lisle. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Lisle may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Lisle last frost occurs after April 15 so be sure to be ready to cover your cardinal flower if you have a late frost.

USDA Zone Info for Lisle

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 Lisle

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