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When to Plant Parsnip in Cass County, ND

Parsnips are a sweet, nutty root vegetable that develops best flavor after exposure to frost. They require a long growing season but reward patient gardeners.

Cass County, North Dakota is in USDA Zone 4a. The average last spring frost is May 11 and the first fall frost is October 2, giving you a growing season of approximately 144 days.

At an elevation of 839 feet, Cass County receives approximately 33.1 inches of rainfall annually with predominantly loam soil. Summer highs average 80ยฐF, so choose short-season varieties of Parsnip to ensure they mature before fall.

Cass County, ND (Zone 4a) Short season
144 days
Last Spring Frost May 11
144 growing days
First Fall Frost October 2

Cass County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (1 days to spare)
Transplant: May 2 🍅 Harvest: Aug 15 – Sep 26
Recommended (50%) ✗ May not fit
Transplant: May 11 🍅 Harvest: Aug 24 – Oct 5
Safe Start (90%) ✗ May not fit
Transplant: May 22 🍅 Harvest: Sep 4 – Oct 16

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 Cass County

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

Soil pH

Your soil pH (6.5โ€“7.6) is more alkaline than Parsnip prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Cass County is excellent for Parsnip โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.4%). Annual compost additions will help Parsnip.

How to Plant Parsnip

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

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.0″/week
Watering frequency Only during dry spells
Season total 53 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Parsnip

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

Month Parsnip Needs Rainfall You Supplement Action
Jan โ€” 0.8" 0" โ„๏ธ Dormant
Feb โ€” 1" 0" โ„๏ธ Dormant
Mar โ€” 2.2" 0" โ„๏ธ Dormant
Apr โ€” 3.6" 0" โ„๏ธ Dormant
May 4.3" 4.2" 0.1" ๐Ÿ’ง Light watering
Jun 4.3" 5.8" 0" โœ… Rainfall sufficient
Jul 4.3" 3.9" 0.4" ๐Ÿ’ง Light watering
Aug 4.3" 4.3" 0" โœ… Rainfall sufficient
Sep 4.3" 2.8" 1.5" ๐Ÿ’ง Light watering
Oct 4.3" 2.3" 2" ๐Ÿ’ง Light watering
Nov โ€” 1.1" 0" โ„๏ธ Dormant
Dec โ€” 0.9" 0" โ„๏ธ Dormant

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

Parsnip 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" โ€” every day above 50ยฐF 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.

Parsnip needs ~1,150 GDD — county provides 1,440 GDD Good fit

Parsnip Planting Timeline โ€” Cass County, ND

Parsnip Planting Calendar

Activity When Date Range
Direct Sow May 4 May 4 โ€“ May 25
Harvest August 17 Aug 17 โ€“ Sep 28
Fall Sowing July 10 Jul 10 โ€“ Jul 24

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

100โ€“130 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 4a

๐Ÿ“† Growing Season

144 days in Cass County

Growing Tips for Parsnip in Cass County

Direct sow Parsnip outdoors after May 11 in Cass County when soil has warmed and frost danger has passed.

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

General growing tips

Use only fresh seed as parsnip seed viability declines rapidly. Sow directly in spring in deeply worked soil. Leave roots in the ground through winter for sweetest flavor.

Companion Planting

Good Companions

Avoid Planting Near

  • Carrots
  • Celery

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Parsnip in Cass County, ND?

Cass County is in Zone 4a with an average last frost of May 11. Plan your Parsnip planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Cass County, ND?

Cass County, North Dakota is in USDA Hardiness Zone 4a. The average last spring frost is May 11 and first fall frost is October 2.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Cass County gardeners in Zone 4a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Cass County, ND. Local conditions may vary. Last updated: April 2026.