When to plant Celeriac in Williamson County, IL
Williamson County sits in USDA Zone 7a. Plant Celeriac between March 27 (after last frost on April 10) and April 17. A second sowing from August 11 to August 25 extends the harvest into fall.
When to Plant Celeriac in Williamson County, IL
Top priorities for Williamson County, Illinois gardeners in June
Your garden in Williamson County, Illinois is working on a schedule, even when you're not. Here's where you should be this June.
Before July arrives, get these ready
- First harvests: celeriac
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.
Williamson County, Illinois is in USDA Zone 7a. 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 1,253 feet, Williamson County receives approximately 38.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Celeriac during the growing season.
Williamson County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-7.2
Drainage
Well Drained
Celeriac Planting Risk Windows
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 Williamson County
How your county's soil matches Celeriac's growing requirements.
Soil pH
Your soil pH (6.2–7.2) overlaps with Celeriac's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Williamson County is excellent for Celeriac — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.4%) — Celeriac will thrive.
How to Plant Celeriac
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Celeriac Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 1.7" | 0" | ❄️ Dormant |
| Feb | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 2.2" | 0" | ❄️ Dormant |
| Apr | 3.9" | 4" | 0" | ✅ Rainfall sufficient |
| May | 3.9" | 4.9" | 0" | ✅ Rainfall sufficient |
| Jun | 3.9" | 4.8" | 0" | ✅ Rainfall sufficient |
| Jul | 3.9" | 4.3" | 0" | ✅ Rainfall sufficient |
| Aug | 3.9" | 3.7" | 0.2" | 💧 Light watering |
| Sep | 3.9" | 3.2" | 0.7" | 💧 Light watering |
| Oct | 3.9" | 2.9" | 1" | 💧 Light watering |
| Nov | — | 2.4" | 0" | ❄️ Dormant |
| Dec | — | 2.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Williamson 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 Planting Timeline — Williamson County, IL
Celeriac Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 6 | Mar 6 – Mar 20 |
| Transplant Outdoors | April 10 | Apr 10 – Apr 24 |
| Direct Sow | March 27 | Mar 27 – Apr 17 |
| Harvest | July 24 | Jul 24 – Aug 28 |
| Fall Sowing | August 11 | Aug 11 – Aug 25 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | — |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.9"/week · Only during dry spells
📅 Days to Maturity
100–120 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 7a
📆 Growing Season
193 days in Williamson County
Growing Tips for Celeriac in Williamson County
Direct sow Celeriac outdoors after April 10 in Williamson 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
Check more plant combinations with our Companion Planting Checker →
Celeriac in Other Locations
Frequently Asked Questions
When should I plant Celeriac in Williamson County, IL?
Williamson County is in Zone 7a with an average last frost of April 10. Plan your Celeriac planting based on this frost date — see the calendar above for exact timing.
What planting zone is Williamson County, IL?
Williamson County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 10 and first fall frost is October 20.
When should I plant Celeriac in Williamson County, IL?
In Williamson County, IL, plant Celeriac after the last frost (around April 10) and before the first frost (around October 20). Best results when soil holds above 50°F.
What growing zone is Williamson County, IL for Celeriac?
Williamson County sits in USDA Zone 7a. Celeriac grows reliably in zones 3a through 9b, so it's a good fit here.
Can Celeriac grow in Williamson County's climate?
Yes — Celeriac grows well in Williamson County's temperate climate. Williamson County averages a 193-day frost-free season, with last frost around April 10 and first frost around October 20.
Your Williamson County Garden Planner — Free
A 22-page printable planner built for Williamson 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.