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 checking out the USDA zone info for Charleston you should be able to determine when to plant flower-of-an-hour.

Planting Calendar for Flower-of-an-Hour

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

You can plant flower-of-an-hour slightly earlier in the year because they are barely cold tolerant.

The earliest that you can plant flower-of-an-hour 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 flower-of-an-hour and expect a good harvest is probably August. You probably don't want to wait any later than that or else your flower-of-an-hour may not have a chance to grow to maturity. You can get started a little bit earlier by starting your flower-of-an-hour indoors.

Last Frost Date

The average date of last frost is April 15 in Charleston. You can expect an average low temperature of -10°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. Since half of the time in Charleston there is a last frost after April 15 be ready to protect your flower-of-an-hour if you have 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.