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When to Plant Cilantro in Iron County, MI

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.

Iron County, Michigan is in USDA Zone 4a. The average last spring frost is May 26 and the first fall frost is September 21, giving you a growing season of approximately 118 days.

At an elevation of 531 feet, Iron County receives approximately 42 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83ยฐF, so choose short-season varieties of Cilantro to ensure they mature before fall.

Iron County, MI (Zone 4a) Short season
118 days
Last Spring Frost May 26
118 growing days
First Fall Frost September 21

Iron County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-6.9

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 โ€” 1.9" 0" โ„๏ธ Dormant
Feb โ€” 2.1" 0" โ„๏ธ Dormant
Mar โ€” 3.2" 0" โ„๏ธ Dormant
Apr โ€” 3.9" 0" โ„๏ธ Dormant
May 4.3" 4.5" 0" โœ… Rainfall sufficient
Jun 4.3" 4.8" 0" โœ… Rainfall sufficient
Jul 4.3" 4.3" 0" โœ… Rainfall sufficient
Aug 4.3" 4.7" 0" โœ… Rainfall sufficient
Sep 4.3" 3.8" 0.5" ๐Ÿ’ง Light watering
Oct โ€” 3" 0" โ„๏ธ Dormant
Nov โ€” 3.3" 0" โ„๏ธ Dormant
Dec โ€” 2.5" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Sep in Iron County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Cilantro Planting Timeline โ€” Iron County, MI

Cilantro Planting Calendar

Activity When Date Range
Start Indoors April 14 Apr 14 โ€“ Apr 28
Transplant Outdoors May 19 May 19 โ€“ Jun 2
Direct Sow May 19 May 19 โ€“ Jun 9
Harvest June 30 Jun 30 โ€“ Sep 1
Fall Sowing June 29 Jun 29 โ€“ Jul 13

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Partial Shade (3-6 hours)

๐Ÿ’ง Water

Moderate โ€” regular watering

๐Ÿ“… Days to Maturity

40โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: N/A

๐Ÿ—บ๏ธ USDA Zone

Zone 4a

๐Ÿ“† Growing Season

118 days in Iron County

Growing Tips for Iron 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 Iron County, MI?

Iron County is in Zone 4a with an average last frost of May 26. Plan your Cilantro planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Iron County, MI?

Iron County, Michigan is in USDA Hardiness Zone 4a. The average last spring frost is May 26 and first fall frost is September 21.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Iron County gardeners in Zone 4a 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 Iron County, MI. Local conditions may vary. Last updated: April 2026.