One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By checking out the USDA zone info for Charleston you should be able to figure out when it's a good idea to plant catharanthus.

Planting Calendar for Catharanthus

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

It's a bad idea to plant catharanthus until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant catharanthus in Charleston 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 catharanthus and expect a good harvest is probably August. If you wait any later than that and your catharanthus may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your catharanthus indoors.

Last Frost Date

In Charleston the average date of last frost happens on April 15. You can expect an average low temperature of 0°F in the coldest months of winter.

Since the USDA zone info for Charleston is just an average the actual date of last frost changes from year to year. Half of the time in Charleston there is a last frost after April 15 so make sure that you are prepared to protect your catharanthus 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.