The USDA Zone info is a great tool for gardeners to help us figure out 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.

You will be able to estimate when you can plant periwinkles by checking out the USDA zone info for Centralia.

Planting Calendar for Periwinkles

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

It's not a good idea to plant periwinkles until after all chance of frost has passed because they require warm weather.

The earliest that you can plant periwinkles in Centralia 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. If you wait any later than that and your periwinkles may not have a chance to grow to maturity. If you are starting your periwinkles indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Centralia. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Centralia is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Centralia you get surprised by a frost after April 15 so always be ready to protect your periwinkles if you have a late frost.

USDA Zone Info for Centralia

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Centralia

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