One of the best tools that you have as gardeners to help us determine 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 common way of making a decision about when it's the best time to plant periwinkles is to look at the USDA zone info for Bainbridge Island.

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 require warm weather which means that it's necessary 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 Bainbridge Island 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. You can get started a little bit earlier by starting your periwinkles indoors.

Last Frost Date

In Bainbridge Island the average date of last frost happens on March 15. In the coldest months of winter you should expect an average low temperature of 15°F.

Since the USDA zone info for Bainbridge Island is not always accurate the actual date of last frost changes from year to year. Half of the time in Bainbridge Island it frosts late in the year after March 15 so be sure to be ready to cover your periwinkles in the event of one of those late frosts.

USDA Zone Info for Bainbridge Island

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 Bainbridge Island

You may be interested in your other planting guides for Bainbridge Island.