Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By looking at the USDA zone info for Vacaville it's a good idea to determine when it's a good idea to plant bok choi.

Planting Calendar for Bok Choi

Frost tolerance for bok choi:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant bok choi a bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant bok choi in Vacaville 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 bok choi and expect a good harvest is probably October. You probably don't want to wait any later than that or else your bok choi may not have a chance to fully mature. If you are starting your bok choi indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Vacaville the average date of last frost happens on February 15. In the coldest months of winter you can expect an average low temperature of 25°F.

Since the USDA zone info for Vacaville is just an average the actual date of last frost will vary from year to year. Half of the time in Vacaville last frost occurs after February 15 so make sure that you are ready to protect your bok choi if you have one of those late frosts.

USDA Zone Info for Vacaville

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 Vacaville

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