One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first chance to plant napa cabbage in San Jose can be determined by referring to the USDA zone info.

Planting Calendar for Napa cabbage

Frost tolerance for napa cabbage:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Napa cabbage can survive in cold weather which tells us that you can plant them quite a bit earlier in the year than more sensitive plants.

The earliest that you can plant napa cabbage in San Jose is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant napa cabbage and expect a good harvest is probably October. You probably don't want to wait any later than that or else your napa cabbage may not have a chance to fully mature. If you are starting your napa cabbage 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 February 15 in San Jose. In the coldest months of winter you can expect an average low temperature of 25°F.

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for San Jose and it will vary from year to year. Half of the time in San Jose last frost occurs after February 15 so be sure to be ready to protect your napa cabbage in the event of a surprise late frost.

USDA Zone Info for San Jose

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 San Jose

You may be interested in your other planting guides for San Jose.