Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Gurnee you can determine when it's the best time to plant fennel by looking at 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 tend to make it in pretty solid 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 fennel in Gurnee 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. Any later than that and your fennel may not have a chance to really do well. Starting your fennel 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 Gurnee. You should expect an average low temperature of -15°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Gurnee is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Gurnee it frosts late in the year after April 15 so be sure to be ready to protect your fennel in the event of a surprise late frost.

USDA Zone Info for Gurnee

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 Gurnee

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