One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to figure out when it's possible to plant lisianthus by referring to the USDA zone info for Charleston.

Planting Calendar for Lisianthus

Frost tolerance for lisianthus:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Lisianthus require warm weather which means that you need to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant lisianthus 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 lisianthus and expect a good harvest is probably September. Any later than that and your lisianthus may not have a chance to fully mature. Starting your lisianthus indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Charleston the average date of last frost happens on February 15. It might get as low as 20°F during the coldest months of winter.

Remember that USDA zone info for Charleston may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Charleston you get surprised by a frost after February 15 so always be ready to cover your lisianthus in the event of one of those late frosts.

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.