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When to Plant Cilantro in Alpena 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.

Alpena County, Michigan is in USDA Zone 5a. The average last spring frost is May 19 and the first fall frost is October 3, giving you a growing season of approximately 137 days.

At an elevation of 984 feet, Alpena County receives approximately 31.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86ยฐF, providing good warmth for Cilantro during the growing season.

Alpena County, MI (Zone 5a) Short season
137 days
Last Spring Frost May 19
137 growing days
First Fall Frost October 3

Alpena County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (41 days to spare)
Start indoors: Apr 8 Transplant: May 6 🍅 Harvest: Jun 17 – Aug 19
Recommended (50%) ✓ Fits season (39 days to spare)
Start indoors: Apr 14 Transplant: May 12 🍅 Harvest: Jun 23 – Aug 25
Safe Start (90%) ✓ Fits season (46 days to spare)
Start indoors: Apr 25 Transplant: May 23 🍅 Harvest: Jul 4 – Sep 5

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 Alpena County

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

Soil pH

Your soil pH (6.0โ€“7.3) overlaps with Cilantro's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.3%) โ€” 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

4
successive plantings in your 137-day season

Sow every 4.6 weeks. Last sowing by Aug 04 to harvest before frost.

For a dedicated fall crop, sow by Jul 25.

Plant Water Budget

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

Water stress score is 6/10 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€” 1.3" 0" โ„๏ธ Dormant
Feb โ€” 1.5" 0" โ„๏ธ Dormant
Mar โ€” 2.2" 0" โ„๏ธ Dormant
Apr โ€” 3.3" 0" โ„๏ธ Dormant
May 2.2" 3.4" 0" โœ… Rainfall sufficient
Jun 2.2" 3.5" 0" โœ… Rainfall sufficient
Jul 2.2" 3.4" 0" โœ… Rainfall sufficient
Aug 2.2" 2.9" 0" โœ… Rainfall sufficient
Sep 2.2" 3" 0" โœ… Rainfall sufficient
Oct 2.2" 2.2" 0" โœ… Rainfall sufficient
Nov โ€” 2.3" 0" โ„๏ธ Dormant
Dec โ€” 2" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Alpena 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 ~725 GDD — county provides 1,986 GDD Excellent fit

Cilantro Planting Timeline โ€” Alpena County, MI

Cilantro Planting Calendar

Activity When Date Range
Start Indoors April 14 Apr 14 โ€“ Apr 28
Transplant Outdoors May 12 May 12 โ€“ May 26
Direct Sow May 5 May 5 โ€“ May 26
Harvest June 23 Jun 23 โ€“ Aug 25
Fall Sowing July 25 Jul 25 โ€“ Aug 8

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 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 Natural rainfall sufficient

๐Ÿ“… Days to Maturity

40โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 5a

๐Ÿ“† Growing Season

137 days in Alpena County

Growing Tips for Cilantro in Alpena County

Direct sow Cilantro outdoors after May 19 in Alpena 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 Alpena County, MI?

Alpena County is in Zone 5a with an average last frost of May 19. Plan your Cilantro planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Alpena County, MI?

Alpena County, Michigan is in USDA Hardiness Zone 5a. The average last spring frost is May 19 and first fall frost is October 3.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Alpena County gardeners in Zone 5a 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 Alpena County, MI. Local conditions may vary. Last updated: April 2026.