The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant calibrachoa in Charleston can be figured out by reviewing the USDA zone info.

Planting Calendar for Calibrachoa

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

Since calibrachoa do ok in moderate cold you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant calibrachoa 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 calibrachoa and expect a good harvest is probably August. If you wait any later than that and your calibrachoa may not have a chance to grow to maturity. If you are starting your calibrachoa indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Charleston. It might get as low as 0°F during the coldest months of winter.

Since the USDA zone info for Charleston is an average the actual date of last frost changes from year to year. Since half of the time in Charleston you get surprised by a frost after April 15 be ready to protect your calibrachoa if you have one of those late frosts.

USDA Zone Info for Charleston

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°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.