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.

The USDA zone info for National City should be reffered to in order to figure out when it's possible 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.

It's probably not a good idea to plant trailing portulaca until after all chance of frost has passed because they require warm weather.

The earliest that you can plant trailing portulaca in National City 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 trailing portulaca and expect a good harvest is probably September. You probably don't want to wait any later than that or else your trailing portulaca may not have a chance to grow to maturity. 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 January 31 in National City. In the coldest months of winter you should expect an average low temperature of 35°F.

Since the USDA zone info for National City may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in National City you get surprised by a frost after January 31 be ready to cover your trailing portulaca if you have one of those late frosts.

USDA Zone Info for National City

Here is the info for USDA Zone 10b.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	35°F
Highest Expected Low	40°F

This means that on a really cold year, the coldest it will get is 35°F. On most years you should be prepared to experience lows near 40°F.

Plants to Grow in National City

You may be interested in your other planting guides for National City.