One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of getting a good idea when it's the best time to plant catharanthus is to look at the USDA zone info for Berlin.

Planting Calendar for Catharanthus

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

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

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

Last Frost Date

On average all chance of frost has passed is on May 15 in Berlin. In the coldest months of winter you should expect an average low temperature of -25°F.

Since the USDA zone info for Berlin is not always accurate the actual date of last frost changes from year to year. Since half of the time in Berlin there is a last frost after May 15 be ready to cover your catharanthus if you have a late frost.

USDA Zone Info for Berlin

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Berlin

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