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When to Plant Cilantro in Aitkin County, MN

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.

Aitkin County, Minnesota is in USDA Zone 3b. The average last spring frost is May 9 and the first fall frost is October 3, giving you a growing season of approximately 147 days.

At an elevation of 1,188 feet, Aitkin County receives approximately 35 inches of rainfall annually with predominantly silt loam soil. Summer highs average 78ยฐF, so choose short-season varieties of Cilantro to ensure they mature before fall.

Aitkin County, MN (Zone 3b) Short season
147 days
Last Spring Frost May 9
147 growing days
First Fall Frost October 3

Aitkin County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (55 days to spare)
Start indoors: Mar 20 Transplant: Apr 24 🍅 Harvest: Jun 5 – Aug 7
Recommended (50%) ✓ Fits season (49 days to spare)
Start indoors: Mar 28 Transplant: May 2 🍅 Harvest: Jun 13 – Aug 15
Safe Start (90%) ✓ Fits season (45 days to spare)
Start indoors: Apr 14 Transplant: May 19 🍅 Harvest: Jun 30 – Sep 1

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 Aitkin County

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

Soil pH

Your soil pH (5.8โ€“7.1) overlaps with Cilantro's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.9%) โ€” Cilantro will thrive.

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

4
successive plantings in your 147-day season

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

For a dedicated fall crop, sow by Jul 11.

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€” 1.4" 0" โ„๏ธ Dormant
Feb โ€” 1.5" 0" โ„๏ธ Dormant
Mar โ€” 2.6" 0" โ„๏ธ Dormant
Apr โ€” 3.6" 0" โ„๏ธ Dormant
May 2.2" 3.7" 0" โœ… Rainfall sufficient
Jun 2.2" 5.1" 0" โœ… Rainfall sufficient
Jul 2.2" 3.9" 0" โœ… Rainfall sufficient
Aug 2.2" 3.5" 0" โœ… Rainfall sufficient
Sep 2.2" 2.8" 0" โœ… Rainfall sufficient
Oct 2.2" 2.7" 0" โœ… Rainfall sufficient
Nov โ€” 2.4" 0" โ„๏ธ Dormant
Dec โ€” 1.9" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Aitkin 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 ~425 GDD — county provides 1,249 GDD Excellent fit

Cilantro Planting Timeline โ€” Aitkin County, MN

Cilantro Planting Calendar

Activity When Date Range
Start Indoors March 28 Mar 28 โ€“ Apr 11
Transplant Outdoors May 2 May 2 โ€“ May 16
Direct Sow May 2 May 2 โ€“ May 23
Harvest June 13 Jun 13 โ€“ Aug 15
Fall Sowing July 11 Jul 11 โ€“ Jul 25

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
May Transplant Outdoors Direct Sow
June Harvest
July Fall Sowing Harvest
August 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 3b

๐Ÿ“† Growing Season

147 days in Aitkin County

Growing Tips for Cilantro in Aitkin County

Direct sow Cilantro outdoors after May 09 in Aitkin 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 Aitkin County, MN?

Aitkin County is in Zone 3b with an average last frost of May 9. Plan your Cilantro planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Aitkin County, MN?

Aitkin County, Minnesota is in USDA Hardiness Zone 3b. The average last spring frost is May 9 and first fall frost is October 3.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Aitkin County gardeners in Zone 3b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Aitkin County, MN. Local conditions may vary. Last updated: April 2026.