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.

By using the USDA zone info for Wheat Ridge you should be able to figure out when you can 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 are very cold tolerant which tells us that you can get them planted much earlier than other frost tender plants.

The earliest that you can plant napa cabbage in Wheat Ridge 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. If you wait any later than that and your napa cabbage may not have a chance to grow to maturity. Starting your napa cabbage indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Wheat Ridge. It might get as low as -10°F during the coldest months of winter.

Keep in mind that USDA zone info for Wheat Ridge is not always accurate and the actual date of last frost changes from year to year. Half of the time in Wheat Ridge it frosts late in the year after April 15 so just be sure to be ready to cover your napa cabbage if you have a late frost.

USDA Zone Info for Wheat Ridge

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Wheat Ridge

You may be interested in your other planting guides for Wheat Ridge.