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When to Plant Cilantro in Graham County, AZ

Graham County, Arizona Zone 8b May

Your May gardening checklist

Each item below is timed to Graham County, Arizona's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost April 6
Avg. first frost November 5
Soil temp (4") 62°F
Watering Critical
Pest pressure Moderate
Daylight 13.7 hrs
  1. Sow cilantro in trays indoors

    A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.

  2. Collect cilantro at their peak

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

A few tasks this May that'll pay off in June
  • First harvests: 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.

Graham County, Arizona is in USDA Zone 8b. The average last spring frost is April 6 and the first fall frost is November 5, giving you a growing season of approximately 213 days.

At an elevation of 2,604 feet, Graham County receives approximately 8 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 98°F, so Cilantro may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Cilantro will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Cilantro successfully. Mulch heavily to conserve soil moisture.

Graham County, AZ (Zone 8b) Long season
213 days
Last Spring Frost April 6
213 growing days
First Fall Frost November 5

Graham County Soil Profile

Soil Type

Sandy Loam

Soil pH

7-8.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (130 days to spare)
Start indoors: Feb 7 Transplant: Mar 7 🍅 Harvest: Apr 18 – Jun 20
Recommended (50%) ✓ Fits season (115 days to spare)
Start indoors: Mar 2 Transplant: Mar 30 🍅 Harvest: May 11 – Jul 13
Safe Start (90%) ✓ Fits season (119 days to spare)
Start indoors: Mar 26 Transplant: Apr 23 🍅 Harvest: Jun 4 – Aug 6

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 Graham County

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

Soil pH

Your soil pH (7.0–8.8) is more alkaline than Cilantro prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Graham County warms quickly in spring but drains fast. Cilantro will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Cilantro.

Organic Matter

Organic matter is low (0.8%). Add 2-3 inches of compost before planting 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

6
successive plantings in your 213-day season

Sow every 4.6 weeks. Last sowing by Sep 06 to harvest before frost.

For a dedicated fall crop, sow by Aug 27.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.2″/week
You supply
0.6″/week
Watering frequency 1-2 times/week
Season total 1,120 gal / 100 sq ft
Drought risk

Water stress score is 10/10 — 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 0.5" 0" ❄️ Dormant
Feb 0.5" 0" ❄️ Dormant
Mar 0.5" 0" ❄️ Dormant
Apr 2.2" 0.3" 1.9" 🚿 Regular watering
May 2.2" 0.2" 2" 🚿 Regular watering
Jun 2.2" 0.3" 1.9" 🚿 Regular watering
Jul 2.2" 1.2" 1" 💧 Light watering
Aug 2.2" 1.8" 0.4" 💧 Light watering
Sep 2.2" 1" 1.2" 🚿 Regular watering
Oct 2.2" 0.8" 1.4" 🚿 Regular watering
Nov 2.2" 0.5" 1.7" 🚿 Regular watering
Dec 0.5" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Nov in Graham 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 ~1,175 GDD — county provides 5,005 GDD Excellent fit

Cilantro Planting Timeline — Graham County, AZ

Cilantro Planting Calendar

Activity When Date Range
Start Indoors March 2 Mar 2 – Mar 16
Transplant Outdoors March 30 Mar 30 – Apr 13
Direct Sow March 23 Mar 23 – Apr 13
Harvest May 11 May 11 – Jul 13
Fall Sowing August 27 Aug 27 – Sep 10

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

0.5"/week · 1-2 times/week

📅 Days to Maturity

40–60 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 8b

📆 Growing Season

213 days in Graham County

Growing Tips for Cilantro in Graham County

Direct sow Cilantro outdoors after April 06 in Graham County when soil has warmed and frost danger has passed.

Sandy soil in Graham County dries quickly — mulch Cilantro with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

Summer highs in Graham County reach 98°F — grow Cilantro as a spring or fall crop. Use shade cloth if planting in summer.

Your generous 213.0-day season in Graham 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 Graham County, AZ?

Graham County is in Zone 8b with an average last frost of April 6. Plan your Cilantro planting based on this frost date — see the calendar above for exact timing.

What planting zone is Graham County, AZ?

Graham County, Arizona is in USDA Hardiness Zone 8b. The average last spring frost is April 6 and first fall frost is November 5.

🌱

Your Graham County Garden Planner — Free

A 24-page printable planner built for Graham County (Zone 8b). 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 Graham County, AZ. 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.