One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Bourbonnais you can estimate when to plant fennel by reviewing the USDA zone info.

Planting Calendar for Fennel

Frost tolerance for fennel:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Fennel do well in cold which tells us that you can plant them a quite a bit earlier than other frost tender plants.

The earliest that you can plant fennel 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 fennel and expect a good harvest is probably September. If you wait any later than that and your fennel may not have a chance to fully mature. Starting your fennel indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Bourbonnais. In the coldest months of winter you can expect an average low temperature of -15°F.

Remember that USDA zone info for Bourbonnais is just an average and the actual date of last frost changes from year to year. Half of the time in Bourbonnais last frost occurs after April 15 so just be sure to be ready to protect your fennel if you have a 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.