Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Louisville should be reffered to in order to figure out when it's possible to plant sunflowers.

Planting Calendar for Sunflowers

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

Sunflowers require warm weather which tells us that you must wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant sunflowers 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 sunflowers and expect a good harvest is probably August. You probably don't want to wait any later than that or else your sunflowers may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your sunflowers indoors.

Last Frost Date

On average the last frost is on March 15 in Louisville. In the coldest months of winter you can expect an average low temperature of 10°F.

Always keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Louisville and it changes from year to year. Since half of the time in Louisville you get surprised by a frost after March 15 be ready to protect your sunflowers if you have 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.