The USDA Zone info is a great tool for gardeners to help us figure out 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 Napa should be reviewed to figure out when it's the best time to plant chinese celery.

Planting Calendar for Chinese celery

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

You can plant chinese celery slightly earlier in the year because they are barely cold tolerant.

The earliest that you can plant chinese celery in Napa 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 chinese celery and expect a good harvest is probably September. Any later than that and your chinese celery may not have a chance to fully mature. If you are starting your chinese celery indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Napa the average date of last frost happens on February 15. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Napa is not always accurate the actual date of last frost is different every year. Since half of the time in Napa it frosts late in the year after February 15 be ready to protect your chinese celery in the event of a surprise late frost.

USDA Zone Info for Napa

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 Napa

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