Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You should be able to figure out when you can plant catharanthus by referring to the USDA zone info for Cary.

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 you must wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant catharanthus in Cary 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. You can get started a few weeks earlier by starting your catharanthus indoors.

Last Frost Date

The average date of last frost is April 15 in Cary. In the coldest months of winter you should expect an average low temperature of -15°F.

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

USDA Zone Info for Cary

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 Cary

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