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.

By using the USDA zone info for Charleston it's possible to figure out when it's a good idea to plant platycodon.

Planting Calendar for Platycodon

Frost tolerance for platycodon:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Platycodon are barely cold tolerant which tells us that you can start planting them slightly earlier than other plants that might not handle the cold.

The earliest that you can plant platycodon 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 platycodon and expect a good harvest is probably August. If you wait any later than that and your platycodon may not have a chance to really do well. If you are starting your platycodon indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Charleston may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Charleston you get a frost after April 15 so make sure that you are prepared to cover your platycodon in the event of a late frost.

USDA Zone Info for Charleston

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°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 -5°F.

Plants to Grow in Charleston

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