The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's possible to figure out when it's possible to plant scallions by referring to the USDA zone info for Palo Alto.

Planting Calendar for Scallions

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

Since scallions are barely cold tolerant you can plant them just a tiny bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant scallions 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 scallions and expect a good harvest is probably September. If you wait any later than that and your scallions may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your scallions indoors.

Last Frost Date

On average all chance of frost has passed is on February 15 in Palo Alto. It might get as low as 25°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Palo Alto is an average and the actual date of last frost changes from year to year. Since half of the time in Palo Alto there is a last frost after February 15 be ready to cover your scallions 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.