The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Zone 4b you can figure out when it's a good idea to plant chinese cabbage by looking at the USDA zone info.

Planting Calendar for Chinese cabbage

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

Chinese cabbage are moderately cold tolerant which tells us that you can plant them earlier than plants that are more sensitive to the cold.

The earliest that you can plant chinese cabbage in Zone 4b is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant chinese cabbage and expect a good harvest is probably August. You probably don't want to wait any later than that or else your chinese cabbage may not have a chance to grow to maturity. Starting your chinese cabbage indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Zone 4b. In the coldest months of winter you should expect an average low temperature of -25°F.

Always keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Zone 4b and it can change quite a bit from year to year. Since half of the time in Zone 4b you get a frost after May 15 be ready to protect your chinese cabbage in the event of a late frost.

USDA Zone Info for Zone 4b

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°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 -20°F.

Plants to Grow in Zone 4b

You may be interested in your other planting guides for Zone 4b.