One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. 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 Zone 12b can be figured out by reviewing 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.

Since periwinkles are not cold tolerant you need to wait until after the last frost has passed before you can plant them.

The earliest that you can plant periwinkles in Zone 12b is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant periwinkles and expect a good harvest is probably November. 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 couple of weeks earlier by starting your periwinkles indoors.

Last Frost Date

In Zone 12b it never frosts. In the coldest months of winter you should expect an average low temperature of 55°F.

Just be sure to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Zone 12b and it is different every year. Since it never frosts in Zone 12b you do not have to be ready to protect your periwinkles in the event of one of those late frosts.

USDA Zone Info for Zone 12b

Here is the info for USDA Zone 12b.

Average Date of Last Frost (spring)	Never
Average Date of First Frost (fall)	Never
Lowest Expected Low	55°F
Highest Expected Low	60°F

This means that on a really cold year, the coldest it will get is 55°F. On most years you should be prepared to experience lows near 60°F.

Plants to Grow in Zone 12b

You may be interested in your other planting guides for Zone 12b.