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When to plant Marigolds in Monroe County, MI

Plant Marigolds in Monroe County after April 27; the prime window is April 27–May 18.

When to Plant Marigolds in Monroe County, MI

Marigolds (Tagetes patula) are warm-season annuals beloved for their cheerful orange, yellow, and red blooms — and for their well-documented ability to repel pest nematodes in vegetable beds. Easy from seed, drought-tolerant once established, and bloom from early summer until the first hard frost.

Monroe County, Michigan is in USDA Zone 6b. The average last spring frost is April 27 and the first fall frost is October 17, giving you a growing season of approximately 173 days.

At an elevation of 1,202 feet, Monroe County receives approximately 40.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Marigolds during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Monroe County, MI (Zone 6b) Moderate season
173 days
Last Spring Frost April 27
173 growing days
First Fall Frost October 17

Monroe County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Marigolds Planting Timeline — Monroe County, MI

Marigolds Planting Calendar

Activity When Date Range
Start Indoors March 16 Mar 16 – Mar 30
Transplant Outdoors April 27 Apr 27 – May 11
Direct Sow April 27 Apr 27 – May 18
Bloom June 22 Jun 22 – Sep 28

Plant 0.3" deep · 10" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

50–70 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 6b

📆 Growing Season

173 days in Monroe County

Growing Tips for Monroe County

Direct-sow after last frost or start indoors 4-6 weeks earlier. Deadhead spent blooms to keep new flowers coming. French marigolds (T. patula) are the most reliable nematode repellents — plant a band around vegetable beds. Tolerate poor soil but bloom best with monthly compost.

Companion Planting

Good Companions

Avoid Planting Near

  • Beans
  • Cabbage

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Marigolds Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Let flower heads dry on plant. Pull dried petals to reveal seeds.
Storage Store in envelopes; viable 3 years at 35°F, under 50% humidity.

Very easy to save. Seeds are the long, thin, dark pieces inside the dried flower head.

Frequently Asked Questions

When should I plant Marigolds in Monroe County, MI?

Monroe County is in Zone 6b with an average last frost of April 27. Plan your Marigolds planting based on this frost date — see the calendar above for exact timing.

What planting zone is Monroe County, MI?

Monroe County, Michigan is in USDA Hardiness Zone 6b. The average last spring frost is April 27 and first fall frost is October 17.

When should I plant Marigolds in Monroe County, MI?

In Monroe County, MI, plant Marigolds after the last frost (around April 27) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is Monroe County, MI for Marigolds?

Monroe County sits in USDA Zone 6b. Marigolds grows reliably in zones 2a through 11b, so it's a good fit here.

Can Marigolds grow in Monroe County's climate?

Yes — Marigolds grows well in Monroe County's temperate climate. Monroe County averages a 173-day frost-free season, with last frost around April 27 and first frost around October 17.

🌱

Your Monroe County Garden Planner — Free

A 22-page printable planner built for Monroe County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

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