Before planting it is a good idea to find your USDA Zone info to figure out 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.

By using the USDA zone info for Chisholm it's possible to determine 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.

You should not plant catharanthus until after the last frost because they do not do well in cold weather.

The earliest that you can plant catharanthus in Chisholm is May. However, you really should wait until June 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 fully mature. You can get started a few weeks earlier by starting your catharanthus indoors.

Last Frost Date

In Chisholm the average date of last frost happens on May 15. It might get as low as -35°F during the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Chisholm and it changes from year to year. Since half of the time in Chisholm last frost occurs after May 15 be ready to cover your catharanthus in the event of one of those late frosts.

USDA Zone Info for Chisholm

Here is the info for USDA Zone 3b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-35°F
Highest Expected Low	-30°F

This means that on a really cold year, the coldest it will get is -35°F. On most years you should be prepared to experience lows near -30°F.

Plants to Grow in Chisholm

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