Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Walnut Creek you can figure out when it's a good idea to plant portulaca by reviewing the USDA zone info.

Planting Calendar for Portulaca

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

It's probably a bad idea to plant portulaca until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant portulaca in Walnut Creek 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 portulaca and expect a good harvest is probably September. If you wait any later than that and your portulaca may not have a chance to fully mature. If you are starting your portulaca indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on February 15 in Walnut Creek. It might get as low as 25°F during the coldest months of winter.

Remember that USDA zone info for Walnut Creek is just an average and the actual date of last frost is different every year. Since half of the time in Walnut Creek it frosts late in the year after February 15 be ready to cover your portulaca in the event of one of those late frosts.

USDA Zone Info for Walnut Creek

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 Walnut Creek

You may be interested in your other planting guides for Walnut Creek.