Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. 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 Clarksville it's a good idea to figure out when to plant catharanthus.

Planting Calendar for Catharanthus

Frost tolerance for catharanthus:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

It's probably not a good idea to plant catharanthus until after the last frost because they are not cold tolerant.

The earliest that you can plant catharanthus in Clarksville 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. You probably don't want to wait any later than that or else your catharanthus may not have a chance to grow to maturity. Starting your catharanthus indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Clarksville. In the coldest months of winter you should expect an average low temperature of 5°F.

Since the USDA zone info for Clarksville is an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Clarksville there is a last frost after April 15 be ready to protect your catharanthus if you have one of those late frosts.

USDA Zone Info for Clarksville

Here is the info for USDA Zone 7b.

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

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Clarksville

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