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When to Plant Cilantro in Grant County, OR

Cilantro is a dual-purpose herb providing fresh leaves (cilantro) and dried seeds (coriander). It bolts quickly in heat, producing flowers beloved by beneficial insects.

Grant County, Oregon is in USDA Zone 5b. The average last spring frost is June 6 and the first fall frost is September 10, giving you a growing season of approximately 96 days.

At an elevation of 2,838 feet, Grant County receives approximately 22.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83ยฐF, so choose short-season varieties of Cilantro to ensure they mature before fall.

Grant County, OR (Zone 5b) Very short season
96 days
Last Spring Frost June 6
96 growing days
First Fall Frost September 10

Grant County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Apr 15 Transplant: May 13 🍅 Harvest: Jun 24 – Aug 26
Recommended (50%) ✗ May not fit
Start indoors: May 2 Transplant: May 30 🍅 Harvest: Jul 11 – Sep 12
Safe Start (90%) ✓ Fits season (2 days to spare)
Start indoors: May 22 Transplant: Jun 19 🍅 Harvest: Jul 31 – Oct 2

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
1.0″/week
Rainfall provides
1.0″/week
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 266 gal / 100 sq ft
Cilantro needs ~612 GDD — county provides 1,176 GDD Excellent fit

Cilantro Planting Timeline โ€” Grant County, OR

Cilantro Planting Calendar

Activity When Date Range
Start Indoors May 2 May 2 โ€“ May 16
Transplant Outdoors May 30 May 30 โ€“ Jun 13
Direct Sow May 23 May 23 โ€“ Jun 13
Fall Sowing July 2 Jul 2 โ€“ Jul 16
Harvest July 11 Jul 11 โ€“ Sep 12

Plant 0.5" deep ยท 8" apart ยท Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

Sun

Partial Shade (3-6 hours)

Water

Moderate โ€” regular watering

Days to Maturity

40โ€“60 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 5b

Growing Season

96 days

Growing Tips for Grant County

Succession sow every 2-3 weeks. Provide afternoon shade in warm weather. Harvest leaves before flowering or allow some plants to go to seed for coriander and self-sowing.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel

Level Up Your Garden

Frequently Asked Questions

When should I plant Cilantro in Grant County, OR?

Grant County is in Zone 5b with an average last frost of June 6. Plan your Cilantro planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Grant County, OR?

Grant County, Oregon is in USDA Hardiness Zone 5b. The average last spring frost is June 6 and first fall frost is September 10.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Grant County gardeners in Zone 5b 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 Grant County, OR. Local conditions may vary. Last updated: April 2026.