Blog

When to Plant Parsnip in Park County, CO

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.

Park County, Colorado is in USDA Zone 4b. The average last spring frost is June 16 and the first fall frost is September 4, giving you a growing season of approximately 80 days.

At an elevation of 7,567 feet, Park County receives approximately 23.3 inches of rainfall annually with predominantly loam soil. Summer highs average 83ยฐF, so choose short-season varieties of Parsnip to ensure they mature before fall.

Park County, CO (Zone 4b) Very short season
80 days
Last Spring Frost June 16
80 growing days
First Fall Frost September 4

Park County Soil Profile

Soil Type

Loam

Soil pH

6.2-7.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Jun 10 🍅 Harvest: Sep 23 – Nov 4
Recommended (50%) ✗ May not fit
Transplant: Jun 16 🍅 Harvest: Sep 29 – Nov 10
Safe Start (90%) ✗ May not fit
Transplant: Jun 26 🍅 Harvest: Oct 9 – Nov 20

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 Park County

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

Soil pH

Your soil pH (6.2โ€“7.6) overlaps with Parsnip's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Parsnip.

Organic Matter

Organic matter is moderate (2.6%). 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
1.2″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 66 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€” 1.5" 0" โ„๏ธ Dormant
Feb โ€” 1.2" 0" โ„๏ธ Dormant
Mar โ€” 1.9" 0" โ„๏ธ Dormant
Apr โ€” 2.2" 0" โ„๏ธ Dormant
May โ€” 3.1" 0" โ„๏ธ Dormant
Jun 4.3" 1.8" 2.5" ๐Ÿšฟ Regular watering
Jul 4.3" 2.2" 2.1" ๐Ÿ’ง Light watering
Aug 4.3" 2.7" 1.6" ๐Ÿ’ง Light watering
Sep 4.3" 1.8" 2.5" ๐Ÿšฟ Regular watering
Oct โ€” 1.8" 0" โ„๏ธ Dormant
Nov โ€” 1.7" 0" โ„๏ธ Dormant
Dec โ€” 1.4" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Junโ€“Sep in Park 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 ~1,409 GDD — county provides 980 GDD May not mature

Parsnip Planting Timeline โ€” Park County, CO

Parsnip Planting Calendar

Activity When Date Range
Direct Sow June 9 Jun 9 โ€“ Jun 30
Harvest September 22 Sep 22 โ€“ Nov 3
Fall Sowing June 12 Jun 12 โ€“ Jun 26

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

Month-by-Month Timeline

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

๐Ÿ—บ๏ธ USDA Zone

Zone 4b

๐Ÿ“† Growing Season

80 days in Park County

Growing Tips for Parsnip in Park County

Direct sow Parsnip outdoors after June 16 in Park County when soil has warmed and frost danger has passed.

Your 80.0-day growing season in Park County is tight for Parsnip (100.0-130.0 days to maturity). Start indoors and choose early-maturing varieties.

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

Park County receives only 23" of rain annually. Parsnip needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

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 Park County, CO?

Park County is in Zone 4b with an average last frost of June 16. Plan your Parsnip planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Park County, CO?

Park County, Colorado is in USDA Hardiness Zone 4b. The average last spring frost is June 16 and first fall frost is September 4.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Park County gardeners in Zone 4b 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 Park County, CO. Local conditions may vary. Last updated: April 2026.