When to Plant Celeriac in Swift County, MN
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.
Swift County, Minnesota is in USDA Zone 4a. The average last spring frost is May 2 and the first fall frost is October 4, giving you a growing season of approximately 155 days.
At an elevation of 1,212 feet, Swift County receives approximately 35.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Celeriac to ensure they mature before fall.
Swift County Soil Profile
Soil Type
Silt Loam
Soil pH
6.3-6.7
Drainage
Well Drained
Plant 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 Swift County
How your county's soil matches Celeriac's growing requirements.
Soil pH
Your soil pH (6.3–6.7) is within Celeriac's preferred range (6.0–7.0).
Soil Texture
The silt loam soil in Swift 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 moderate (3.8%). Annual compost additions will help Celeriac.
How to Plant Celeriac
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Plant Water Budget
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 | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | — | 2.9" | 0" | ❄️ Dormant |
| May | 3.9" | 4.6" | 0" | ✅ Rainfall sufficient |
| Jun | 3.9" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jul | 3.9" | 3.8" | 0.1" | 💧 Light watering |
| Aug | 3.9" | 3.6" | 0.3" | 💧 Light watering |
| Sep | 3.9" | 2.8" | 1.1" | 💧 Light watering |
| Oct | 3.9" | 2.3" | 1.6" | 💧 Light watering |
| Nov | — | 2.6" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Swift 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 — Swift 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 12 | Jul 12 – Jul 26 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| 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
155 days in Swift County
Growing Tips for Celeriac in Swift County
Direct sow Celeriac outdoors after May 02 in Swift 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 Swift County, MN?
Swift 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 Swift County, MN?
Swift County, Minnesota is in USDA Hardiness Zone 4a. The average last spring frost is May 2 and first fall frost is October 4.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Swift County gardeners in Zone 4a organize planting dates, track what's growing, and never miss a planting window.
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