One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. 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 Monrovia should be reviewed to figure out when you can 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.

Since bok choi do well in moderate cold you can plant them a little bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant bok choi in Monrovia 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 fully mature. If you are starting your bok choi 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 January 31 in Monrovia. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for Monrovia is just an average the actual date of last frost will vary from year to year. Half of the time in Monrovia last frost occurs after January 31 so make sure that you are ready to cover your bok choi if you have a surprise late frost.

USDA Zone Info for Monrovia

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 Monrovia

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