Before planting it is a good idea to find your USDA Zone info to figure out 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 Marseilles should be read to estimate when it's the best time to plant catharanthus.

Planting Calendar for Catharanthus

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

Since catharanthus do not do well in cold weather it's important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant catharanthus in Marseilles 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 fully mature. You can get started a couple of weeks earlier by starting your catharanthus indoors.

Last Frost Date

On average the last frost is on April 15 in Marseilles. It might get as low as -15°F during the coldest months of winter.

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

USDA Zone Info for Marseilles

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Marseilles

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