One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

The USDA zone info for Rio Vista should be reffered to in order to figure out when to plant trailing portulaca.

Planting Calendar for Trailing Portulaca

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

Since trailing portulaca require warm weather it is necessary to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant trailing portulaca in Rio Vista 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 trailing portulaca and expect a good harvest is probably September. Any later than that and your trailing portulaca may not have a chance to really do well. If you are starting your trailing portulaca indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Rio Vista. In the coldest months of winter you should expect an average low temperature of 25°F.

Remember that USDA zone info for Rio Vista may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Rio Vista last frost occurs after February 15 so make sure that you are prepared to cover your trailing portulaca if you have a late frost.

USDA Zone Info for Rio Vista

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 Rio Vista

You may be interested in your other planting guides for Rio Vista.