Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of determining when it's the best time to plant bok choi is to use the USDA zone info for El Cajon.

Planting Calendar for Bok Choi

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

Bok Choi are one of those plants that can tolerate a little bit of cold weather which tells us that you can plant them earlier than more sensitive plants.

The earliest that you can plant bok choi in El Cajon 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. If you wait any later than that and your bok choi may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your bok choi indoors.

Last Frost Date

In El Cajon the average date of last frost happens on January 31. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for El Cajon is an average the actual date of last frost is different every year. Half of the time in El Cajon last frost occurs after January 31 so be sure to be ready to cover your bok choi in the event of one of those late frosts.

USDA Zone Info for El Cajon

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in El Cajon

You may be interested in your other planting guides for El Cajon.