One of the best tools that you have as gardeners to help us estimate 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.

In Urbana you can figure out when to plant cardinal flower by referring to 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.

Cardinal Flower require warm weather which tells us that it is necessary to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant cardinal flower in Urbana 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 grow to maturity. If you are starting your cardinal flower indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Urbana. You should expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Urbana is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Urbana 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 Urbana

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 Urbana

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