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When to Plant Cilantro in Otero County, CO

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.

Otero County, Colorado is in USDA Zone 6a. The average last spring frost is April 26 and the first fall frost is October 9, giving you a growing season of approximately 166 days.

At an elevation of 4,145 feet, Otero County receives approximately 14.2 inches of rainfall annually with predominantly loam soil. Summer highs average 90ยฐF, providing good warmth for Cilantro during the growing season. With low rainfall, drip irrigation is essential for growing Cilantro successfully. Mulch heavily to conserve soil moisture.

Otero County, CO (Zone 6a) Moderate season
166 days
Last Spring Frost April 26
166 growing days
First Fall Frost October 9

Otero County Soil Profile

Soil Type

Loam

Soil pH

6.4-8.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (68 days to spare)
Start indoors: Mar 18 Transplant: Apr 15 🍅 Harvest: May 27 – Jul 29
Recommended (50%) ✓ Fits season (68 days to spare)
Start indoors: Mar 22 Transplant: Apr 19 🍅 Harvest: May 31 – Aug 2
Safe Start (90%) ✓ Fits season (66 days to spare)
Start indoors: Apr 8 Transplant: May 6 🍅 Harvest: Jun 17 – Aug 19

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 Otero County

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

Soil pH

Your soil pH (6.4โ€“8.1) is more alkaline than Cilantro prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Otero County is excellent for Cilantro โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.5%). Annual compost additions will help Cilantro.

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

4
successive plantings in your 166-day season

Sow every 4.6 weeks. Last sowing by Aug 10 to harvest before frost.

For a dedicated fall crop, sow by Jul 31.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.4″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 249 gal / 100 sq ft
Drought risk

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

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 โ€” 1" 0" โ„๏ธ Dormant
Feb โ€” 0.9" 0" โ„๏ธ Dormant
Mar โ€” 1.2" 0" โ„๏ธ Dormant
Apr 2.2" 1.4" 0.8" ๐Ÿ’ง Light watering
May 2.2" 1.5" 0.7" ๐Ÿ’ง Light watering
Jun 2.2" 1.1" 1.1" ๐Ÿšฟ Regular watering
Jul 2.2" 1.5" 0.7" ๐Ÿ’ง Light watering
Aug 2.2" 1.3" 0.9" ๐Ÿ’ง Light watering
Sep 2.2" 1.1" 1.1" ๐Ÿšฟ Regular watering
Oct 2.2" 1.2" 1" ๐Ÿ’ง Light watering
Nov โ€” 1" 0" โ„๏ธ Dormant
Dec โ€” 0.9" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Otero County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 ~875 GDD — county provides 2,905 GDD Excellent fit

Cilantro Planting Timeline โ€” Otero County, CO

Cilantro Planting Calendar

Activity When Date Range
Start Indoors March 22 Mar 22 โ€“ Apr 5
Transplant Outdoors April 19 Apr 19 โ€“ May 3
Direct Sow April 12 Apr 12 โ€“ May 3
Harvest May 31 May 31 โ€“ Aug 2
Fall Sowing July 31 Jul 31 โ€“ Aug 14

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

0.5"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

40โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 6a

๐Ÿ“† Growing Season

166 days in Otero County

Growing Tips for Cilantro in Otero County

Direct sow Cilantro outdoors after April 26 in Otero County when soil has warmed and frost danger has passed.

Your generous 166.0-day season in Otero County allows multiple plantings of Cilantro. Sow every 20.0 days for continuous harvest.

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 Otero County, CO?

Otero County is in Zone 6a with an average last frost of April 26. Plan your Cilantro planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Otero County, CO?

Otero County, Colorado is in USDA Hardiness Zone 6a. The average last spring frost is April 26 and first fall frost is October 9.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Otero County gardeners in Zone 6a 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 Otero County, CO. Local conditions may vary. Last updated: April 2026.