Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can estimate when it's possible to plant periwinkles in Alameda by using 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.

Since periwinkles do not do well in cold weather it is important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant periwinkles in Alameda 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 grow to maturity. You can get started a little bit earlier by starting your periwinkles indoors.

Last Frost Date

On average the last frost is on January 31 in Alameda. You should expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for Alameda is just an average the actual date of last frost will vary from year to year. Since half of the time in Alameda it frosts late in the year after January 31 be ready to cover your periwinkles if you have a late frost.

USDA Zone Info for Alameda

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 Alameda

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