Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of figuring out when to plant periwinkles is to use the USDA zone info for King.

Planting Calendar for Periwinkles

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

You should not plant periwinkles until after the last frost because they require warm weather.

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

Last Frost Date

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

Keep in mind that USDA zone info for King is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in King you get a frost after April 15 be ready to cover your periwinkles if you have one of those late frosts.

USDA Zone Info for King

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 King

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