One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Dickinson you can figure out when to plant catharanthus by looking at the USDA zone info.

Planting Calendar for Catharanthus

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

It's probably a bad idea to plant catharanthus until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant catharanthus in Dickinson 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. You probably don't want to wait any later than that or else your catharanthus may not have a chance to grow to maturity. You can get started a little bit earlier by starting your catharanthus indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Dickinson. In the coldest months of winter you can expect an average low temperature of -30°F.

Since the USDA zone info for Dickinson is an average the actual date of last frost changes from year to year. Half of the time in Dickinson there is a last frost after May 15 so make sure that you are ready to cover your catharanthus if you have one of those late frosts.

USDA Zone Info for Dickinson

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Dickinson

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