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When to Plant Cilantro in Snohomish County, WA

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.

Snohomish County, Washington is in USDA Zone 8a. The average last spring frost is March 25 and the first fall frost is November 2, giving you a growing season of approximately 222 days.

At an elevation of 230 feet, Snohomish County receives approximately 50.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90Β°F, providing good warmth for Cilantro during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Cilantro root diseases.

Snohomish County, WA (Zone 8a) Long season
222 days
Last Spring Frost March 25
222 growing days
First Fall Frost November 2

Snohomish County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.8

Drainage

Well Drained

Monthly Watering Guide for Cilantro

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

Month Cilantro Needs Rainfall You Supplement Action
Jan β€” 7.7" 0" ❄️ Dormant
Feb β€” 5.6" 0" ❄️ Dormant
Mar 4.3" 5" 0" βœ… Rainfall sufficient
Apr 4.3" 3.6" 0.7" πŸ’§ Light watering
May 4.3" 2.6" 1.7" πŸ’§ Light watering
Jun 4.3" 1.6" 2.7" 🚿 Regular watering
Jul 4.3" 0.7" 3.6" 🚿 Regular watering
Aug 4.3" 1" 3.3" 🚿 Regular watering
Sep 4.3" 2" 2.3" 🚿 Regular watering
Oct 4.3" 4.2" 0.1" πŸ’§ Light watering
Nov 4.3" 8" 0" βœ… Rainfall sufficient
Dec β€” 8.5" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Snohomish County). Supplement amounts are based on average rainfall β€” actual needs vary with temperature, soil, and mulching.

Cilantro Planting Timeline β€” Snohomish County, WA

Cilantro Planting Calendar

Activity When Date Range
Start Indoors February 18 Feb 18 – Mar 4
Transplant Outdoors March 18 Mar 18 – Apr 1
Direct Sow March 11 Mar 11 – Apr 1
Harvest April 29 Apr 29 – Jul 1
Fall Sowing August 24 Aug 24 – Sep 7

Plant 0.5" deep Β· 8" apart Β· Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

β˜€οΈ Sun

Partial Shade (3-6 hours)

πŸ’§ Water

Moderate β€” regular watering

πŸ“… Days to Maturity

40–60 days

πŸ§ͺ Soil pH

Needs 6–7 Β· Your soil: N/A

πŸ—ΊοΈ USDA Zone

Zone 8a

πŸ“† Growing Season

222 days in Snohomish County

Growing Tips for Snohomish 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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Cilantro in Snohomish County, WA?

Snohomish County is in Zone 8a with an average last frost of March 25. Plan your Cilantro planting based on this frost date β€” see the calendar above for exact timing.

What planting zone is Snohomish County, WA?

Snohomish County, Washington is in USDA Hardiness Zone 8a. The average last spring frost is March 25 and first fall frost is November 2.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner β€” designed to help Snohomish County gardeners in Zone 8a 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 Snohomish County, WA. Local conditions may vary. Last updated: April 2026.