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.

You can figure out when to plant catharanthus in Vienna by reviewing the USDA zone info.

Planting Calendar for Catharanthus

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

Catharanthus do not do well in cold weather which tells us that you must wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant catharanthus in Vienna 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 grow to maturity. 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 Vienna. In the coldest months of winter you can expect an average low temperature of -5°F.

Since the USDA zone info for Vienna may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Vienna you get surprised by a 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 Vienna

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Vienna

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