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 best time to plant petunias in Palo Alto should be figured out by checking out the USDA zone info.

Planting Calendar for Petunias

Frost tolerance for petunias:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since petunias do ok in moderate cold you can plant them slightly earlier in the year than other plants that might not handle the cold.

The earliest that you can plant petunias in Palo Alto 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 petunias and expect a good harvest is probably September. You probably don't want to wait any later than that or else your petunias may not have a chance to really do well. Starting your petunias indoors is a great way to get them started a little bit earlier.

Last Frost Date

In Palo Alto the average date of last frost happens on February 15. You can expect an average low temperature of 25°F in the coldest months of winter.

Since the USDA zone info for Palo Alto is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Palo Alto you get a frost after February 15 be ready to protect your petunias in the event of one of those late frosts.

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.