Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant periwinkles in Signal Mountain can be determined by reviewing the USDA zone info.

Planting Calendar for Periwinkles

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

Since periwinkles are not cold tolerant it is necessary to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant periwinkles in Signal Mountain 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. If you wait any later than that and your periwinkles may not have a chance to grow to maturity. If you are starting your periwinkles indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Signal Mountain. You should expect an average low temperature of 0°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Signal Mountain is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Signal Mountain there is a last frost after April 15 be ready to protect your periwinkles if you have a late frost.

USDA Zone Info for Signal Mountain

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 Signal Mountain

You may be interested in your other planting guides for Signal Mountain.