One of the best tools that you have as gardeners to help us figure out 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.

By reviewing the USDA zone info for Palo Alto you will be able to determine when it's a good idea to plant portulaca.

Planting Calendar for Portulaca

Frost tolerance for portulaca:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

You really shouldn't plant portulaca until after the last frost because they are not cold tolerant.

The earliest that you can plant portulaca in Palo Alto 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 really do well. Starting your portulaca indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost has passed is on February 15 in Palo Alto. In the coldest months of winter you should expect an average low temperature of 25°F.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Palo Alto and it is different every year. Half of the time in Palo Alto you get surprised by a frost after February 15 so be sure to be ready to protect your portulaca in the event of a late frost.

USDA Zone Info for Palo Alto

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 Palo Alto

You may be interested in your other planting guides for Palo Alto.