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.

The USDA zone info for Bonne Terre can be reviewed to estimate when to plant catharanthus.

Planting Calendar for Catharanthus

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

Catharanthus require warm weather which means that it is necessary to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant catharanthus in Bonne Terre 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. Any later than that and your catharanthus may not have a chance to really do well. If you are starting your catharanthus indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Bonne Terre. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Bonne Terre is not always accurate the actual date of last frost will vary from year to year. Half of the time in Bonne Terre you get surprised by a frost after April 15 so make sure that you are prepared to protect your catharanthus if you have a surprise late frost.

USDA Zone Info for Bonne Terre

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 Bonne Terre

You may be interested in your other planting guides for Bonne Terre.