One of the first steps you take when you are estimating 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.

By checking out the USDA zone info for Belle Plaine it's possible to figure out when it's possible to plant periwinkles.

Planting Calendar for Periwinkles

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

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

The earliest that you can plant periwinkles in Belle Plaine is May. However, you really should wait until June 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 fully mature. 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 May 15 in Belle Plaine. In the coldest months of winter you should expect an average low temperature of -25°F.

Since the USDA zone info for Belle Plaine is an average the actual date of last frost will vary from year to year. Since half of the time in Belle Plaine it frosts late in the year after May 15 be ready to protect your periwinkles if you have a late frost.

USDA Zone Info for Belle Plaine

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Belle Plaine

You may be interested in your other planting guides for Belle Plaine.