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When to Plant Cilantro in Klamath County, OR

Klamath County, Oregon Zone 6b May

Klamath County, Oregon gardeners: here's your May plan

A quick May briefing for Klamath County, Oregon gardeners — what's urgent, what's next, and what can wait.

Avg. last frost June 13
Avg. first frost September 21
Soil temp (4") 63°F
Watering Moderate
Pest pressure Low
Daylight 14.4 hrs
  1. Direct-sow cilantro

    Sow every 2 weeks for a continuous harvest. A single big planting means a single big glut.

Before June arrives, get these ready
  • Transplants going out: cilantro

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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.

Klamath County, Oregon is in USDA Zone 6b. The average last spring frost is June 13 and the first fall frost is September 21, giving you a growing season of approximately 100 days.

At an elevation of 142 feet, Klamath County receives approximately 48.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Cilantro to ensure they mature before fall.

Klamath County, OR (Zone 6b) Short season
100 days
Last Spring Frost June 13
100 growing days
First Fall Frost September 21

Klamath County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Apr 25 Transplant: May 23 🍅 Harvest: Jul 4 – Sep 5
Recommended (50%) ✓ Fits season (2 days to spare)
Start indoors: May 9 Transplant: Jun 6 🍅 Harvest: Jul 18 – Sep 19
Safe Start (90%) ✓ Fits season (16 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.

Soil Compatibility in Klamath County

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

Soil pH

Your soil pH (5.5–6.3) is more acidic than Cilantro prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Klamath County is excellent for Cilantro — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Cilantro.

Organic Matter

Organic matter is excellent (5.1%) — Cilantro will thrive.

How to Plant Cilantro

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Cilantro

2
successive plantings in your 100-day season

Sow every 4.6 weeks. Last sowing by Jul 23 to harvest before frost.

For a dedicated fall crop, sow by Jul 13.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
2.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Cilantro

Cilantro needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Cilantro Needs Rainfall You Supplement Action
Jan 7.4" 0" ❄️ Dormant
Feb 5.2" 0" ❄️ Dormant
Mar 4.8" 0" ❄️ Dormant
Apr 3.3" 0" ❄️ Dormant
May 3" 0" ❄️ Dormant
Jun 2.2" 1.8" 0.4" 💧 Light watering
Jul 2.2" 0.9" 1.3" 🚿 Regular watering
Aug 2.2" 0.8" 1.4" 🚿 Regular watering
Sep 2.2" 2.1" 0.1" 💧 Light watering
Oct 4.8" 0" ❄️ Dormant
Nov 7.7" 0" ❄️ Dormant
Dec 6.9" 0" ❄️ Dormant

Water needs are for active growing months only (Jun–Sep in Klamath County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Cilantro 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" — every day above 50°F 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.

Cilantro needs ~612 GDD — county provides 1,225 GDD Excellent fit

Cilantro Planting Timeline — Klamath County, OR

Cilantro Planting Calendar

Activity When Date Range
Start Indoors May 9 May 9 – May 23
Transplant Outdoors June 6 Jun 6 – Jun 20
Direct Sow May 30 May 30 – Jun 20
Harvest July 18 Jul 18 – Sep 19
Fall Sowing July 13 Jul 13 – Jul 27

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

40–60 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 6b

📆 Growing Season

100 days in Klamath County

Growing Tips for Cilantro in Klamath County

Direct sow Cilantro outdoors after June 13 in Klamath County when soil has warmed and frost danger has passed.

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

General growing tips

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 Klamath County, OR?

Klamath County is in Zone 6b with an average last frost of June 13. Plan your Cilantro planting based on this frost date — see the calendar above for exact timing.

What planting zone is Klamath County, OR?

Klamath County, Oregon is in USDA Hardiness Zone 6b. The average last spring frost is June 13 and first fall frost is September 21.

🌱

Your Klamath County Garden Planner — Free

A 24-page printable planner built for Klamath County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Klamath County, OR. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.