One of the first steps you take when you are making a decision about your gardening schedule is find your 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.

It's possible to estimate when to plant periwinkles by using the USDA zone info for Antioch.

Planting Calendar for Periwinkles

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

Periwinkles do not do well in cold weather which means that it is necessary to wait until it warms up after all chance of frost has passed before you can plant them.

The earliest that you can plant periwinkles in Antioch 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. Any later than that and your periwinkles may not have a chance to fully mature. Starting your periwinkles indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is February 15 in Antioch. In the coldest months of winter you should expect an average low temperature of 25°F.

Since the USDA zone info for Antioch is just an average the actual date of last frost will vary from year to year. Half of the time in Antioch you get a frost after February 15 so be sure to be ready to cover your periwinkles in the event of a surprise late frost.

USDA Zone Info for Antioch

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 Antioch

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