The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Charleston can be used to estimate when it's possible to plant black eyed susans.

Planting Calendar for Black Eyed Susans

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

Black Eyed Susans require warm weather which tells us that it is important to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant black eyed susans in Charleston is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant black eyed susans and expect a good harvest is probably September. Any later than that and your black eyed susans may not have a chance to fully mature. If you are starting your black eyed susans indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Charleston. You can expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Charleston is just an average the actual date of last frost will vary from year to year. Since half of the time in Charleston it frosts late in the year after February 15 be ready to protect your black eyed susans in the event of a late frost.

USDA Zone Info for Charleston

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Charleston

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