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When to plant Celeriac in Benton County, MN

In Benton County, plant Celeriac in spring between April 25 and May 16, once soil temps hold above 50°F. Benton County's last frost averages May 2, so be cautious and check the 10-day forecast before planting tender crops. For a fall crop, sow between July 14 and July 28 — roughly 100–120 days before the first frost on October 6.

When to Plant Celeriac in Benton County, MN

Benton County, Minnesota Zone 4a July

July to-do list for Benton County, Minnesota

If you only do a handful of things in the garden this July, make it these. They're sequenced around your zone's frost timing.

Avg. last frost May 2
Avg. first frost October 6
Soil temp (4") 72°F
Watering Low
Pest pressure High
Daylight 15.2 hrs
  1. Kick off the fall garden with celeriac

    Your first frost is about 9 weeks away — plenty of time for these to mature.

Before August arrives, get these ready
  • 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.

Benton County, Minnesota is in USDA Zone 4a. The average last spring frost is May 2 and the first fall frost is October 6, giving you a growing season of approximately 157 days.

At an elevation of 1,178 feet, Benton County receives approximately 39 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.

Benton County, MN (Zone 4a) Moderate season
157 days
Last Spring Frost May 2
157 growing days
First Fall Frost October 6

Benton County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7

Drainage

Well Drained

Celeriac Planting Risk Windows

Early Start (70% safe) ✓ Fits season (16 days to spare)
Start indoors: Mar 15 Transplant: Apr 26 🍅 Harvest: Aug 9 – Sep 13
Recommended (50%) ✓ Fits season (17 days to spare)
Start indoors: Mar 21 Transplant: May 2 🍅 Harvest: Aug 15 – Sep 19
Safe Start (90%) ✓ Fits season (13 days to spare)
Start indoors: Apr 7 Transplant: May 19 🍅 Harvest: Sep 1 – Oct 6

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 Benton County

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

Soil pH

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

Soil Texture

The silt loam soil in Benton 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 (4.9%) — Celeriac will thrive.

How to Plant Celeriac

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

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Celeriac Water Budget

Plant needs
0.9″/week
Rainfall provides
1.0″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 177 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 1.6" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 3" 0" ❄️ Dormant
Apr 3.4" 0" ❄️ Dormant
May 3.9" 4.1" 0" ✅ Rainfall sufficient
Jun 3.9" 5" 0" ✅ Rainfall sufficient
Jul 3.9" 4.5" 0" ✅ Rainfall sufficient
Aug 3.9" 4.2" 0" ✅ Rainfall sufficient
Sep 3.9" 3.3" 0.6" 💧 Light watering
Oct 3.9" 3.3" 0.6" 💧 Light watering
Nov 2.7" 0" ❄️ Dormant
Dec 2.5" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Benton 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 2,041 GDD Excellent fit

Celeriac Planting Timeline — Benton County, MN

Celeriac Planting Calendar

Activity When Date Range
Start Indoors March 21 Mar 21 – Apr 4
Transplant Outdoors May 2 May 2 – May 16
Direct Sow April 25 Apr 25 – May 16
Harvest August 15 Aug 15 – Sep 19
Fall Sowing July 14 Jul 14 – Jul 28

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors Direct Sow
May Transplant Outdoors Direct Sow
June
July Fall Sowing
August Harvest
September Harvest
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: ideal

🗺️ USDA Zone

Zone 4a

📆 Growing Season

157 days in Benton County

Growing Tips for Celeriac in Benton County

Direct sow Celeriac outdoors after May 02 in Benton 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 →

Frequently Asked Questions

When should I plant Celeriac in Benton County, MN?

Benton County is in Zone 4a with an average last frost of May 2. Plan your Celeriac planting based on this frost date — see the calendar above for exact timing.

What planting zone is Benton County, MN?

Benton County, Minnesota is in USDA Hardiness Zone 4a. The average last spring frost is May 2 and first fall frost is October 6.

When should I plant Celeriac in Benton County, MN?

In Benton County, MN, plant Celeriac after the last frost (around May 2) and before the first frost (around October 6). Best results when soil holds above 50°F.

What growing zone is Benton County, MN for Celeriac?

Benton County sits in USDA Zone 4a. Celeriac grows reliably in zones 3a through 9b, so it's a good fit here.

Can Celeriac grow in Benton County's climate?

Yes — Celeriac grows well in Benton County's temperate climate. Benton County averages a 157-day frost-free season, with last frost around May 2 and first frost around October 6.

🌱

Your Benton County Garden Planner — Free

A 22-page printable planner built for Benton County (Zone 4a). 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 Benton County, MN. Local conditions may vary. Last updated: July 2026.

Sources & credits

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