When to Plant Fennel in Zion, IL

One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

It's a good idea to estimate when it's possible to plant fennel by referring to the USDA zone info for Zion.


Planting Calendar for Fennel

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

Since fennel are one of those plants that can tolerate quite a bit of cold weather you can plant them much earlier in the year than plants that are more sensitive to the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant fennel
Possibly ok, but a risky time to plant fennel
Probably not a good time to plant fennel

The earliest that you can plant fennel in Zion 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 grow to maturity. Starting your fennel indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Since the USDA zone info for Zion is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Zion last frost occurs after April 15 be ready to protect your fennel if you have a surprise late frost.

USDA Zone Info for Zion

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 Zion

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