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When to Plant Cilantro in Golden Valley County, MT

Golden Valley County, Montana Zone 4b May

May in the garden — Golden Valley County, Montana

Your garden in Golden Valley County, Montana is working on a schedule, even when you're not. Here's where you should be this May.

Avg. last frost May 22
Avg. first frost September 20
Soil temp (4") 30°F
Watering Moderate
Pest pressure Low
Daylight 14.8 hrs
  1. Plant out cilantro

    Bring a watering can to the bed. Each transplant gets a drink the moment it's in the ground, not ten minutes later.

  2. Outdoor sowing time: cilantro

    Rake a smooth bed, make a shallow furrow, drop seeds at the spacing on the packet, water gently, walk away.

To set up a strong June, finish these tasks
  • First harvests: cilantro
  • Fall sowing: 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.

Golden Valley County, Montana is in USDA Zone 4b. The average last spring frost is May 22 and the first fall frost is September 20, giving you a growing season of approximately 121 days.

At an elevation of 7,917 feet, Golden Valley County receives approximately 25 inches of rainfall annually with predominantly loam soil. Summer highs average 83°F, so choose short-season varieties of Cilantro to ensure they mature before fall.

Golden Valley County, MT (Zone 4b) Short season
121 days
Last Spring Frost May 22
121 growing days
First Fall Frost September 20
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Golden Valley County Soil Profile

Soil Type

Loam

Soil pH

6.8-8.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (19 days to spare)
Start indoors: Apr 6 Transplant: May 11 🍅 Harvest: Jun 22 – Aug 24
Recommended (50%) ✓ Fits season (23 days to spare)
Start indoors: Apr 10 Transplant: May 15 🍅 Harvest: Jun 26 – Aug 28
Safe Start (90%) ✓ Fits season (23 days to spare)
Start indoors: Apr 26 Transplant: May 31 🍅 Harvest: Jul 12 – Sep 13

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 Golden Valley County

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

Soil pH

Your soil pH (6.8–8.3) is more alkaline than Cilantro prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Cilantro.

How to Plant Cilantro

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

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Succession Planting Cilantro

3
successive plantings in your 121-day season

Sow every 4.6 weeks. Last sowing by Jul 22 to harvest before frost.

For a dedicated fall crop, sow by Jun 28.

Plant Water Budget

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

Water stress score is 6/10 — 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 2" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 2.1" 0" ❄️ Dormant
Apr 2.6" 0" ❄️ Dormant
May 2.2" 3" 0" ✅ Rainfall sufficient
Jun 2.2" 1.9" 0.3" 💧 Light watering
Jul 2.2" 2.3" 0" ✅ Rainfall sufficient
Aug 2.2" 2.4" 0" ✅ Rainfall sufficient
Sep 2.2" 1.9" 0.3" 💧 Light watering
Oct 2.4" 0" ❄️ Dormant
Nov 1.7" 0" ❄️ Dormant
Dec 1.3" 0" ❄️ Dormant

Water needs are for active growing months only (May–Sep in Golden Valley 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 1,482 GDD Excellent fit

Cilantro Planting Timeline — Golden Valley County, MT

Cilantro Planting Calendar

Activity When Date Range
Start Indoors April 10 Apr 10 – Apr 24
Transplant Outdoors May 15 May 15 – May 29
Direct Sow May 15 May 15 – Jun 5
Harvest June 26 Jun 26 – Aug 28
Fall Sowing June 28 Jun 28 – Jul 12

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

Month-by-Month Timeline

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

🗺️ USDA Zone

Zone 4b

📆 Growing Season

121 days in Golden Valley County

Growing Tips for Cilantro in Golden Valley County

Direct sow Cilantro outdoors after May 22 in Golden Valley 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 Golden Valley County, MT?

Golden Valley County is in Zone 4b with an average last frost of May 22. Plan your Cilantro planting based on this frost date — see the calendar above for exact timing.

What planting zone is Golden Valley County, MT?

Golden Valley County, Montana is in USDA Hardiness Zone 4b. The average last spring frost is May 22 and first fall frost is September 20.

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Your Golden Valley County Garden Planner — Free

A 24-page printable planner built for Golden Valley County (Zone 4b). 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 Golden Valley County, MT. 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.