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 first opportunity to plant cardinal flower in Granite City should be estimated by using the USDA zone info.

Planting Calendar for Cardinal Flower

Frost tolerance for cardinal flower:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

It's not a good idea to plant cardinal flower until after all chance of frost has passed because they require warm weather.

The earliest that you can plant cardinal flower in Granite City 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 really do well. Starting your cardinal flower indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Granite City. It might get as low as -5°F during the coldest months of winter.

It's important to remember that USDA zone info for Granite City is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Granite City there is a last frost after April 15 so make sure that you are prepared to protect your cardinal flower if you have a late frost.

USDA Zone Info for Granite City

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Granite City

You may be interested in your other planting guides for Granite City.