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When to Plant Celery in Lemhi County, ID

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.

Lemhi County, Idaho is in USDA Zone 4b. The average last spring frost is June 9 and the first fall frost is September 14, giving you a growing season of approximately 97 days.

At an elevation of 6,743 feet, Lemhi County receives approximately 12.6 inches of rainfall annually with predominantly loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Celery to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Celery successfully. Mulch heavily to conserve soil moisture.

Lemhi County, ID (Zone 4b) Very short season
97 days
Last Spring Frost June 9
97 growing days
First Fall Frost September 14

Lemhi County Soil Profile

Soil Type

Loam

Soil pH

6.2-8.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Apr 2 Transplant: May 14 🍅 Harvest: Aug 6 – Oct 1
Recommended (50%) ✗ May not fit
Start indoors: Apr 28 Transplant: Jun 9 🍅 Harvest: Sep 1 – Oct 27
Safe Start (90%) ✗ May not fit
Start indoors: May 14 Transplant: Jun 25 🍅 Harvest: Sep 17 – Nov 12

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
0.6″/week
You supply
1.2″/week
Watering frequency 2-3 times/week
Season total 989 gal / 100 sq ft
Drought risk

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

Celery needs ~1,300 GDD — county provides 1,261 GDD Tight fit

Celery Planting Timeline โ€” Lemhi County, ID

Celery Planting Calendar

Activity When Date Range
Start Indoors April 28 Apr 28 โ€“ May 12
Transplant Outdoors June 9 Jun 9 โ€“ Jun 23
Direct Sow June 2 Jun 2 โ€“ Jun 23
Fall Sowing June 22 Jun 22 โ€“ Jul 6
Harvest September 1 Sep 1 โ€“ Oct 27

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Start Indoors
May Start Indoors
June Transplant Outdoors Direct Sow Fall Sowing
July Fall Sowing
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 4b

Growing Season

97 days

Growing Tips for Lemhi 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 Lemhi County, ID?

Lemhi County is in Zone 4b with an average last frost of June 9. Plan your Celery planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Lemhi County, ID?

Lemhi County, Idaho is in USDA Hardiness Zone 4b. The average last spring frost is June 9 and first fall frost is September 14.

๐ŸŒฑ

Plan Your Garden with Confidence

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