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When to plant Fennel in Gallatin County, IL

The best window to plant Fennel in Gallatin County, is April 13–May 4, when soil warms to 50°F. Last frost typically hits April 6; first frost October 30.

When to Plant Fennel in Gallatin County, IL

Florence fennel is grown for its swollen bulb-like stem base, which has a mild anise flavor. It is crisp raw in salads and sweet when roasted or braised.

Gallatin County, Illinois is in USDA Zone 7a. The average last spring frost is April 6 and the first fall frost is October 30, giving you a growing season of approximately 207 days.

At an elevation of 1,391 feet, Gallatin County receives approximately 37 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Fennel during the growing season.

Gallatin County, IL (Zone 7a) Long season
207 days
Last Spring Frost April 6
207 growing days
First Fall Frost October 30

Gallatin County Soil Profile

Soil Type

Silt Loam

Soil pH

6.3-6.8

Drainage

Well Drained

Monthly Watering Guide for Fennel

Fennel needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Fennel Needs Rainfall You Supplement Action
Jan 1.7" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 4.3" 3.3" 1" 💧 Light watering
May 4.3" 4.2" 0.1" 💧 Light watering
Jun 4.3" 4.4" 0" ✅ Rainfall sufficient
Jul 4.3" 4.5" 0" ✅ Rainfall sufficient
Aug 4.3" 3.7" 0.6" 💧 Light watering
Sep 4.3" 3.3" 1" 💧 Light watering
Oct 4.3" 2.7" 1.6" 💧 Light watering
Nov 2.6" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Gallatin County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Fennel Planting Timeline — Gallatin County, IL

Fennel Planting Calendar

Activity When Date Range
Start Indoors February 16 Feb 16 – Mar 2
Transplant Outdoors April 20 Apr 20 – May 4
Direct Sow April 13 Apr 13 – May 4
Harvest June 22 Jun 22 – Aug 3

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors
April Transplant Outdoors Direct Sow
May Transplant Outdoors Direct Sow
June Harvest
July Harvest
August Harvest
September
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 5.5–7 · Your soil: N/A

🗺️ USDA Zone

Zone 7a

📆 Growing Season

207 days in Gallatin County

Growing Tips for Gallatin County

Direct sow in late summer for fall harvest to reduce bolting. Hill soil around bulbs as they enlarge. Harvest when bulbs are tennis-ball sized before they elongate.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Peppers
  • Beans

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Fennel in Gallatin County, IL?

Gallatin County is in Zone 7a with an average last frost of April 6. Plan your Fennel planting based on this frost date — see the calendar above for exact timing.

What planting zone is Gallatin County, IL?

Gallatin County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 6 and first fall frost is October 30.

When should I plant Fennel in Gallatin County, IL?

In Gallatin County, IL, plant Fennel after the last frost (around April 6) and before the first frost (around October 30). Best results when soil holds above 50°F.

What growing zone is Gallatin County, IL for Fennel?

Gallatin County sits in USDA Zone 7a. Fennel grows reliably in zones 4a through 10b, so it's a good fit here.

Can Fennel grow in Gallatin County's climate?

Yes — Fennel grows well in Gallatin County's temperate climate. Gallatin County averages a 207-day frost-free season, with last frost around April 6 and first frost around October 30.

🌱

Your Gallatin County Garden Planner — Free

A 22-page printable planner built for Gallatin County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Gallatin County, IL. Local conditions may vary. Last updated: June 2026.

Sources & credits

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