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When to plant Marigolds in Swift County, MN

Plant Marigolds in Swift County, when soil hits 50°F — usually May 9. Continue planting through May 30 for the spring crop.

When to Plant Marigolds in Swift County, MN

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.

Swift County, Minnesota is in USDA Zone 4b. The average last spring frost is May 2 and the first fall frost is October 4, giving you a growing season of approximately 155 days.

At an elevation of 1,212 feet, Swift County receives approximately 35.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Marigolds to ensure they mature before fall.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Swift County, MN (Zone 4b) Moderate season
155 days
Last Spring Frost May 2
155 growing days
First Fall Frost October 4

Swift County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Marigolds Planting Timeline — Swift County, MN

Marigolds Planting Calendar

Activity When Date Range
Start Indoors March 21 Mar 21 – Apr 4
Transplant Outdoors May 9 May 9 – May 23
Direct Sow May 9 May 9 – May 30
Bloom July 4 Jul 4 – Sep 19

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Start Indoors
May Transplant Outdoors Direct Sow
June
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 4b

📆 Growing Season

155 days in Swift County

Growing Tips for Swift 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 Swift County, MN?

Swift County is in Zone 4b with an average last frost of May 2. Plan your Marigolds planting based on this frost date — see the calendar above for exact timing.

What planting zone is Swift County, MN?

Swift County, Minnesota is in USDA Hardiness Zone 4b. The average last spring frost is May 2 and first fall frost is October 4.

When should I plant Marigolds in Swift County, MN?

In Swift County, MN, plant Marigolds after the last frost (around May 2) and before the first frost (around October 4). Best results when soil holds above 50°F.

What growing zone is Swift County, MN for Marigolds?

Swift County sits in USDA Zone 4b. Marigolds grows reliably in zones 2a through 11b, so it's a good fit here.

Can Marigolds grow in Swift County's climate?

Yes — Marigolds grows well in Swift County's temperate climate. Swift County averages a 155-day frost-free season, with last frost around May 2 and first frost around October 4.

🌱

Your Swift County Garden Planner — Free

A 22-page printable planner built for Swift 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.

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 Swift County, MN. Local conditions may vary. Last updated: June 2026.

Sources & credits

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