One of the first steps you take when you are figuring out 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.

In Alhambra you can estimate when to plant periwinkles by checking out 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 not a good idea to plant periwinkles until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant periwinkles in Alhambra 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. Any later than that and your periwinkles may not have a chance to really do well. You can get started a few weeks earlier by starting your periwinkles indoors.

Last Frost Date

In Alhambra the average date of last frost happens on January 31. In the coldest months of winter you should expect an average low temperature of 30°F.

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 Alhambra and it will vary from year to year. Half of the time in Alhambra there is a last frost after January 31 so be sure to be ready to cover your periwinkles in the event of a late frost.

USDA Zone Info for Alhambra

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 Alhambra

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