One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to determine when it's the best time to plant periwinkles by referring to the USDA zone info for Whiting.

Planting Calendar for Periwinkles

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

Since periwinkles require warm weather you must wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant periwinkles in Whiting 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. You can get started a few weeks earlier by starting your periwinkles indoors.

Last Frost Date

In Whiting the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -10°F.

Since the USDA zone info for Whiting is just an average the actual date of last frost will vary from year to year. Since half of the time in Whiting you get surprised by a frost after April 15 be ready to cover your periwinkles in the event of a surprise late frost.

USDA Zone Info for Whiting

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 Whiting

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