Before planting it is a good idea to find your USDA Zone info to estimate 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.

The first opportunity to plant napa cabbage in Colby should be determined by referring to the USDA zone info.

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 can survive in a bit of cold which means that you can plant them earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant napa cabbage in Colby 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 napa cabbage and expect a good harvest is probably September. Any later than that and your napa cabbage may not have a chance to fully mature. You can get started a few weeks earlier by starting your napa cabbage indoors.

Last Frost Date

The average date of last frost is April 15 in Colby. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Colby is an average the actual date of last frost changes from year to year. Since half of the time in Colby you get a frost after April 15 be ready to protect your napa cabbage in the event of one of those late frosts.

USDA Zone Info for Colby

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 Colby

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