One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. 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 making a decision about when to plant periwinkles is to refer to the USDA zone info for Zone 8b.

Planting Calendar for Periwinkles

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

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

The earliest that you can plant periwinkles in Zone 8b 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. Any later than that and 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 March 15 in Zone 8b. In the coldest months of winter you can expect an average low temperature of 15°F.

Always keep in mind that USDA zone info for Zone 8b 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 Zone 8b you get a frost after March 15 be ready to protect your periwinkles if you have a surprise late frost.

USDA Zone Info for Zone 8b

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Zone 8b

You may be interested in your other planting guides for Zone 8b.