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

By checking out the USDA zone info for Huntsville you should be able to determine 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.

Periwinkles require warm weather which tells us that it's important to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant periwinkles in Huntsville 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 fully mature. If you are starting your periwinkles indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Huntsville. You should expect an average low temperature of 5°F in the coldest months of winter.

Always keep in mind that USDA zone info for Huntsville is an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Huntsville you get a frost after April 15 be ready to cover your periwinkles if you have a surprise late frost.

USDA Zone Info for Huntsville

Here is the info for USDA Zone 7b.

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

Plants to Grow in Huntsville

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