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

A way of getting a good idea when it's possible to plant bok choi is to look at the USDA zone info for Zone 5b.

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 tend to make it in mild cold which means that you can plant them a little bit earlier in the year than more sensitive plants.

The earliest that you can plant bok choi in Zone 5b 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 bok choi and expect a good harvest is probably September. You probably don't want to wait any later than that or else 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

The average date of last frost is April 15 in Zone 5b. You can expect an average low temperature of -15°F in the coldest months of winter.

Always keep in mind that USDA zone info for Zone 5b is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Zone 5b last frost occurs after April 15 so be sure to be ready to protect your bok choi if you have a surprise late frost.

USDA Zone Info for Zone 5b

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Zone 5b

You may be interested in your other planting guides for Zone 5b.