One of the first steps you take when you are getting a good idea 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.

In Louisville you can determine when it's a good idea to plant cardinal flower by looking at 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.

You can not plant cardinal flower until after the last frost because they do not do well in cold weather.

The earliest that you can plant cardinal flower in Louisville 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. If you wait any later than that and your cardinal flower may not have a chance to grow to maturity. Starting your cardinal flower indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Louisville the average date of last frost happens on March 15. It might get as low as 10°F during the coldest months of winter.

It's important to remember that USDA zone info for Louisville may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Louisville last frost occurs after March 15 be ready to cover your cardinal flower in the event of a late frost.

USDA Zone Info for Louisville

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

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

Plants to Grow in Louisville

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