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

The first chance to plant napa cabbage in Casper should be estimated by looking at 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.

You can plant napa cabbage much earlier in the year because they are very cold tolerant.

The earliest that you can plant napa cabbage in Casper 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 fully mature. If you are starting your napa cabbage indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Casper. In the coldest months of winter you can expect an average low temperature of -20°F.

Since the USDA zone info for Casper is not always accurate the actual date of last frost will vary from year to year. Half of the time in Casper you get a frost 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 Casper

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Casper

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