One of the first steps you take when you are determining your gardening schedule is find your 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.

One way of making a decision about when it's possible to plant trailing portulaca is to use the USDA zone info for Atwater.

Planting Calendar for Trailing Portulaca

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

You can not plant trailing portulaca until after the last frost has passed because they are not cold tolerant.

The earliest that you can plant trailing portulaca in Atwater 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. 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 couple of weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Atwater. It might get as low as 20°F during the coldest months of winter.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Atwater and it can change quite a bit from year to year. Half of the time in Atwater there is a last frost after February 15 so make sure that you are ready to protect your trailing portulaca in the event of a surprise late frost.

USDA Zone Info for Atwater

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Atwater

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