The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant periwinkles in Porterville should be determined by using the USDA zone info.

Planting Calendar for Periwinkles

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

You should not plant periwinkles until after the last frost because they are not cold tolerant.

The earliest that you can plant periwinkles in Porterville is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant periwinkles and expect a good harvest is probably September. 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 little bit earlier by starting your periwinkles indoors.

Last Frost Date

The average date of last frost is February 15 in Porterville. You can expect an average low temperature of 25°F in the coldest months of winter.

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Porterville and it can change quite a bit from year to year. Half of the time in Porterville you get a frost after February 15 so be sure to be ready to protect your periwinkles in the event of a surprise late frost.

USDA Zone Info for Porterville

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Porterville

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