One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You will be able to figure out when it's the best time to plant napa cabbage by reviewing the USDA zone info for Bismarck.

Planting Calendar for Napa cabbage

Frost tolerance for napa cabbage:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Napa cabbage do well in cold which tells us that you can start planting them much earlier than more sensitive plants.

The earliest that you can plant napa cabbage in Bismarck 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 napa cabbage and expect a good harvest is probably August. You probably don't want to wait any later than that or else your napa cabbage may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your napa cabbage indoors.

Last Frost Date

In Bismarck the average date of last frost happens on May 15. In the coldest months of winter you should expect an average low temperature of -30°F.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Bismarck and it can change quite a bit from year to year. Since half of the time in Bismarck it frosts late in the year after May 15 be ready to protect your napa cabbage if you have one of those late frosts.

USDA Zone Info for Bismarck

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°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 -25°F.

Plants to Grow in Bismarck

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