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

A way of figuring out when it's the best time to plant periwinkles is to refer to the USDA zone info for Calimesa.

Planting Calendar for Periwinkles

Frost tolerance for periwinkles:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

You should not plant periwinkles until after the last frost because they require warm weather.

The earliest that you can plant periwinkles in Calimesa 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 grow to maturity. You can get started a couple of weeks earlier by starting your periwinkles indoors.

Last Frost Date

The average date of last frost is February 15 in Calimesa. It might get as low as 25°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Calimesa is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Calimesa it frosts late in the year after February 15 so make sure that you are ready to cover your periwinkles if you have a surprise late frost.

USDA Zone Info for Calimesa

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 Calimesa

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