One of the best tools that you have as gardeners to help us estimate 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.

By looking at the USDA zone info for Vienna it's possible to determine when to plant periwinkles.

Planting Calendar for Periwinkles

Frost tolerance for periwinkles:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Periwinkles do not do well in cold weather which means that it is important to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant periwinkles 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 periwinkles and expect a good harvest is probably August. You probably don't want to wait any later than that or else your periwinkles may not have a chance to fully mature. You can get started a few weeks earlier by starting your periwinkles 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 0°F.

Always keep in mind that USDA zone info for Vienna is just an average and the actual date of last frost will vary from year to year. Since half of the time in Vienna you get surprised by a frost after April 15 be ready to cover your periwinkles if you have one of those late frosts.

USDA Zone Info for Vienna

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in Vienna

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