The USDA Zone info is a great tool for gardeners to help us determine your gardening 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 determine when it's the best time to plant portulaca in Riverside by referring to 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 not a good idea to plant portulaca until after the last frost because they do not do well in cold weather.

The earliest that you can plant portulaca in Riverside is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant portulaca and expect a good harvest is probably August. Any later than that and your portulaca may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your portulaca indoors.

Last Frost Date

The average date of last frost is April 15 in Riverside. In the coldest months of winter you can expect an average low temperature of -10°F.

Always keep in mind that USDA zone info for Riverside is an average and the actual date of last frost is different every year. Half of the time in Riverside it frosts late in the year after April 15 so just be sure to be ready to protect your portulaca in the event of a late frost.

USDA Zone Info for Riverside

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Riverside

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