The USDA Zone info is a great tool for gardeners to help us figure out 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 opportunity to plant periwinkles in Somerton can be estimated by reviewing the USDA zone info.

Planting Calendar for Periwinkles

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

It's a bad idea to plant periwinkles until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant periwinkles in Somerton is February. However, you really should wait until March 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. If you wait any later than that and your periwinkles may not have a chance to really do well. If you are starting your periwinkles indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on January 31 in Somerton. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for Somerton is just an average the actual date of last frost is different every year. Since half of the time in Somerton there is a last frost after January 31 be ready to protect your periwinkles in the event of a late frost.

USDA Zone Info for Somerton

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Somerton

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