The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Austin can be looked at to figure out when it's the best time to plant periwinkles.

Planting Calendar for Periwinkles

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

It's probably not a good idea to plant periwinkles until after the last frost because they require warm weather.

The earliest that you can plant periwinkles in Austin 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. Any later than that and your periwinkles may not have a chance to grow to maturity. Starting your periwinkles indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Austin. In the coldest months of winter you should expect an average low temperature of -10°F.

Keep in mind that USDA zone info for Austin may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Austin it frosts late in the year after April 15 so always be ready to cover your periwinkles if you have one of those late frosts.

USDA Zone Info for Austin

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Austin

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