One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By reviewing the USDA zone info for Columbia you will be able to determine when it's a good idea to plant napa cabbage.

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 tend to make it in pretty solid cold which tells us that you can plant them earlier in the year than other plants that might not handle the cold.

The earliest that you can plant napa cabbage in Columbia 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. You probably don't want to wait any later than that or else your napa cabbage may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your napa cabbage indoors.

Last Frost Date

In Columbia the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -5°F.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Columbia and it is different every year. Half of the time in Columbia it frosts late in the year after April 15 so make sure that you are prepared to protect your napa cabbage in the event of one of those late frosts.

USDA Zone Info for Columbia

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Columbia

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