The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The USDA zone info for Gig Harbor should be looked at to estimate when it's a good idea to plant periwinkles.

Planting Calendar for Periwinkles

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

Periwinkles are not cold tolerant which tells us that you must wait until it warms up after the last frost before you can plant them.

The earliest that you can plant periwinkles in Gig Harbor 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 fully mature. You can get started a couple of weeks earlier by starting your periwinkles indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on March 15 in Gig Harbor. You can expect an average low temperature of 15°F in the coldest months of winter.

Since the USDA zone info for Gig Harbor may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Gig Harbor it frosts late in the year after March 15 be ready to protect your periwinkles in the event of one of those late frosts.

USDA Zone Info for Gig Harbor

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 Gig Harbor

You may be interested in your other planting guides for Gig Harbor.