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When to plant Celeriac in Dewitt,

In Zone 6a (Dewitt), direct-sow Celeriac between April 1 and April 22 for spring, after the April 15 last-frost mark. A second sowing from August 8 to August 22 extends the harvest into fall.

When to Plant Celeriac in Dewitt, IL

Dewitt, IL Zone 6a June

Your June planting checklist for Dewitt, IL

Each item below is timed to Dewitt, IL's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost April 15
Avg. first frost October 17
Soil temp (4") 71°F
Watering Low
Pest pressure High
Daylight 14.8 hrs
July will be here before you know it — start on
  • First harvests: celeriac

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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.

Dewitt, Illinois is in USDA Zone 6a. The average last spring frost is April 15 and the first fall frost is October 17, giving you a growing season of approximately 185 days.

At an elevation of 801 feet, DeWitt County receives approximately 31.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Celeriac to ensure they mature before fall.

Dewitt, IL (Zone 6a) Moderate season
185 days
Last Spring Frost April 15
185 growing days
First Fall Frost October 17
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Dewitt Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-7

Drainage

Well Drained

Celeriac Planting Risk Windows

Early Start (70% safe) ✓ Fits season (44 days to spare)
Start indoors: Mar 6 Transplant: Apr 10 🍅 Harvest: Jul 24 – Aug 28
Recommended (50%) ✓ Fits season (45 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: Jul 29 – Sep 2
Safe Start (90%) ✓ Fits season (47 days to spare)
Start indoors: Mar 24 Transplant: Apr 28 🍅 Harvest: Aug 11 – Sep 15

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Dewitt

How your county's soil matches Celeriac's growing requirements.

Soil pH

Your soil pH (6.1–7.0) is within Celeriac's preferred range (6.0–7.0).

Soil Texture

The silt loam soil in DeWitt County is excellent for Celeriac — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Celeriac is a heavy drinker but your soil drains very quickly. Mulch heavily and consider drip irrigation.

Organic Matter

Organic matter is excellent (5.0%) — Celeriac will thrive.

How to Plant Celeriac

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Celeriac Water Budget

Plant needs
0.9″/week
Rainfall provides
0.7″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 738 gal / 100 sq ft

Monthly Watering Guide for Celeriac

Celeriac needs approximately 0.9 inches of water per week (3.9" per month). Here's how your county's rainfall compares month by month.

Month Celeriac Needs Rainfall You Supplement Action
Jan 1.4" 0" ❄️ Dormant
Feb 1.2" 0" ❄️ Dormant
Mar 2.3" 0" ❄️ Dormant
Apr 3.9" 2.6" 1.3" 💧 Light watering
May 3.9" 4.1" 0" ✅ Rainfall sufficient
Jun 3.9" 4.3" 0" ✅ Rainfall sufficient
Jul 3.9" 3.2" 0.7" 💧 Light watering
Aug 3.9" 3.6" 0.3" 💧 Light watering
Sep 3.9" 2.7" 1.2" 💧 Light watering
Oct 3.9" 2.3" 1.6" 💧 Light watering
Nov 2.1" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

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

Celeriac Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Celeriac needs ~1,430 GDD — county provides 2,405 GDD Excellent fit

Celeriac Planting Timeline — Dewitt, IL

Celeriac Planting Calendar

Activity When Date Range
Start Indoors March 11 Mar 11 – Mar 25
Transplant Outdoors April 15 Apr 15 – Apr 29
Direct Sow April 1 Apr 1 – Apr 22
Harvest July 29 Jul 29 – Sep 2
Fall Sowing August 8 Aug 8 – Aug 22

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.9"/week · 1-2 times/week

📅 Days to Maturity

100–120 days

🧪 Soil pH

Needs 6–7 · Your soil: ideal

🗺️ USDA Zone

Zone 6a

📆 Growing Season

185 days in DeWitt County

Growing Tips for Celeriac in Dewitt

Direct sow Celeriac outdoors after April 15 in DeWitt County when soil has warmed and frost danger has passed.

Common pests for Celeriac in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

General growing tips

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 →

When should I plant Celeriac in Dewitt, ?

In Dewitt, , plant Celeriac after the last frost (around April 15) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is Dewitt, for Celeriac?

Dewitt sits in USDA Zone 6a. Celeriac grows reliably in zones 3a through 9b, so it's a good fit here.

Can Celeriac grow in Dewitt's climate?

Yes — Celeriac grows well in Dewitt's temperate climate. Dewitt averages a 185-day frost-free season, with last frost around April 15 and first frost around October 17.

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Your DeWitt County Garden Planner — Free

A 22-page printable planner built for DeWitt County (Zone 6a). 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 DeWitt County, IL. Local conditions may vary. Last updated: June 2026.