One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. 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 Southfield should be used to determine when to plant periwinkles.

Planting Calendar for Periwinkles

Frost tolerance for periwinkles:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since periwinkles require warm weather it's important to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant periwinkles in Southfield 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 really do well. Starting your periwinkles indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Southfield. In the coldest months of winter you can expect an average low temperature of -10°F.

Since the USDA zone info for Southfield may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Southfield it frosts late in the year after April 15 so make sure that you are prepared to protect your periwinkles if you have a late frost.

USDA Zone Info for Southfield

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 Southfield

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