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When to Plant Celeriac in Franklin County, IL

Celeriac is a celery relative grown for its knobby, flavorful root rather than its stalks. It has a rich celery flavor and is excellent roasted, mashed, or in soups.

Franklin County, Illinois is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 20, giving you a growing season of approximately 193 days.

At an elevation of 747 feet, Franklin County receives approximately 37.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89ยฐF, providing good warmth for Celeriac during the growing season.

Franklin County, IL (Zone 6b) Moderate season
193 days
Last Spring Frost April 10
193 growing days
First Fall Frost October 20

Franklin County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.1

Drainage

Well Drained

Monthly Watering Guide for Celeriac

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

Month Celeriac Needs Rainfall You Supplement Action
Jan โ€” 1.4" 0" โ„๏ธ Dormant
Feb โ€” 1.7" 0" โ„๏ธ Dormant
Mar โ€” 2.7" 0" โ„๏ธ Dormant
Apr 4.3" 3.9" 0.4" ๐Ÿ’ง Light watering
May 4.3" 4.4" 0" โœ… Rainfall sufficient
Jun 4.3" 4.7" 0" โœ… Rainfall sufficient
Jul 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Aug 4.3" 4.1" 0.2" ๐Ÿ’ง Light watering
Sep 4.3" 2.9" 1.4" ๐Ÿ’ง Light watering
Oct 4.3" 3.1" 1.2" ๐Ÿ’ง Light watering
Nov โ€” 2.6" 0" โ„๏ธ Dormant
Dec โ€” 2.3" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Franklin County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Celeriac Planting Timeline โ€” Franklin County, IL

Celeriac Planting Calendar

Activity When Date Range
Start Indoors March 6 Mar 6 โ€“ Mar 20
Transplant Outdoors April 10 Apr 10 โ€“ Apr 24
Direct Sow March 27 Mar 27 โ€“ Apr 17
Harvest July 24 Jul 24 โ€“ Aug 28
Fall Sowing August 11 Aug 11 โ€“ Aug 25

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

High โ€” keep soil consistently moist

๐Ÿ“… Days to Maturity

100โ€“120 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: N/A

๐Ÿ—บ๏ธ USDA Zone

Zone 6b

๐Ÿ“† Growing Season

193 days in Franklin County

Growing Tips for Franklin County

Start seeds indoors 10-12 weeks before last frost. Remove side roots as they develop to encourage a single large bulb. Harvest after a light frost for best flavor.

Companion Planting

Good Companions

Avoid Planting Near

  • Carrots
  • Parsnip

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Celeriac in Franklin County, IL?

Franklin County is in Zone 6b with an average last frost of April 10. Plan your Celeriac planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Franklin County, IL?

Franklin County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 10 and first fall frost is October 20.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Franklin County gardeners in Zone 6b organize planting dates, track what's growing, and never miss a planting window.

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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 Franklin County, IL. Local conditions may vary. Last updated: April 2026.