One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of getting a good idea when to plant napa cabbage is to look at the USDA zone info for International Falls.

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

The earliest that you can plant napa cabbage in International Falls 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. 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 couple of weeks earlier.

Last Frost Date

The average date of last frost is May 15 in International Falls. It might get as low as -40°F during the coldest months of winter.

Since the USDA zone info for International Falls is just an average the actual date of last frost changes from year to year. Half of the time in International Falls you get a frost after May 15 so be sure to be ready to protect your napa cabbage if you have one of those late frosts.

USDA Zone Info for International Falls

Here is the info for USDA Zone 3a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-40°F
Highest Expected Low	-35°F

This means that on a really cold year, the coldest it will get is -40°F. On most years you should be prepared to experience lows near -35°F.

Plants to Grow in International Falls

You may be interested in your other planting guides for International Falls.