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When to Plant Celery in Jackson County, CO

Celery is a marshland plant that requires consistent moisture and cool temperatures to produce crisp, flavorful stalks. It is a rewarding but demanding garden crop.

Jackson County, Colorado is in USDA Zone 3b. The average last spring frost is June 13 and the first fall frost is September 4, giving you a growing season of approximately 83 days.

At an elevation of 5,388 feet, Jackson County receives approximately 20.9 inches of rainfall annually with predominantly loam soil. Summer highs average 80ยฐF, so choose short-season varieties of Celery to ensure they mature before fall.

Jackson County, CO (Zone 3b) Very short season
83 days
Last Spring Frost June 13
83 growing days
First Fall Frost September 4

Jackson County Soil Profile

Soil Type

Loam

Soil pH

6.6-8.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Apr 27 Transplant: Jun 8 🍅 Harvest: Aug 31 – Oct 12
Recommended (50%) ✗ May not fit
Start indoors: May 2 Transplant: Jun 13 🍅 Harvest: Sep 5 – Oct 17
Safe Start (90%) ✗ May not fit
Start indoors: May 14 Transplant: Jun 25 🍅 Harvest: Sep 17 – Oct 29

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.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
1.1″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 392 gal / 100 sq ft
Drought risk

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

Celery needs ~1,000 GDD — county provides 830 GDD May not mature

Celery Planting Timeline โ€” Jackson County, CO

Celery Planting Calendar

Activity When Date Range
Start Indoors May 2 May 2 โ€“ May 16
Transplant Outdoors June 13 Jun 13 โ€“ Jun 27
Direct Sow June 6 Jun 6 โ€“ Jun 27
Fall Sowing June 12 Jun 12 โ€“ Jun 26
Harvest September 5 Sep 5 โ€“ Oct 17

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

High โ€” keep soil consistently moist

Days to Maturity

80โ€“120 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 3b

Growing Season

83 days

Growing Tips for Jackson County

Start seeds indoors 10-12 weeks before last frost. Keep soil consistently moist and never let it dry out. Blanch stalks by mounding soil or using collars for milder flavor.

Companion Planting

Good Companions

Avoid Planting Near

  • Carrots
  • Parsnip

Level Up Your Garden

Frequently Asked Questions

When should I plant Celery in Jackson County, CO?

Jackson County is in Zone 3b with an average last frost of June 13. Plan your Celery planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Jackson County, CO?

Jackson County, Colorado is in USDA Hardiness Zone 3b. The average last spring frost is June 13 and first fall frost is September 4.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Jackson County gardeners in Zone 3b organize planting dates, track what's growing, and never miss a planting window.

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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 Jackson County, CO. Local conditions may vary. Last updated: April 2026.