The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By checking out the USDA zone info for Bourbonnais it's a good idea to estimate when it's the best time 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 quite a bit of cold which tells us that you can plant them a lot earlier in the year than other frost tender plants.

The earliest that you can plant napa cabbage in Bourbonnais 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. Starting your napa cabbage indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Bourbonnais. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Bourbonnais may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Bourbonnais last frost occurs after April 15 so always be ready to cover your napa cabbage in the event of a surprise late frost.

USDA Zone Info for Bourbonnais

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 Bourbonnais

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