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When to plant Fennel (herb) in Itasca County, MN

Plant Fennel (herb) in Itasca County after May 10; the prime window is May 3–May 24. A second sowing from July 9 to July 23 extends the harvest into fall.

When to Plant Fennel (herb) in Itasca County, MN

Herb fennel is grown for its aromatic leaves, stalks, and seeds rather than a bulb. It has a strong anise flavor and its flowers attract beneficial insects.

Itasca County, Minnesota is in USDA Zone 4a. The average last spring frost is May 10 and the first fall frost is October 1, giving you a growing season of approximately 144 days.

At an elevation of 506 feet, Itasca County receives approximately 40.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Fennel (herb) to ensure they mature before fall.

Itasca County, MN (Zone 4a) Short season
144 days
Last Spring Frost May 10
144 growing days
First Fall Frost October 1

Itasca County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Fennel (herb) Planting Timeline — Itasca County, MN

Fennel (herb) Planting Calendar

Activity When Date Range
Start Indoors March 29 Mar 29 – Apr 12
Transplant Outdoors May 3 May 3 – May 17
Direct Sow May 3 May 3 – May 24
Harvest July 5 Jul 5 – Sep 13
Fall Sowing July 9 Jul 9 – Jul 23

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 5.5–7 · Your soil: N/A

🗺️ USDA Zone

Zone 4a

📆 Growing Season

144 days in Itasca County

Growing Tips for Itasca County

Direct sow in spring or fall. Unlike Florence fennel, herb fennel does not form a bulb. Harvest fronds as needed and seeds when they turn brown. Self-sows readily.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Peppers
  • Green Beans

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Fennel (herb) in Itasca County, MN?

Itasca County is in Zone 4a with an average last frost of May 10. Plan your Fennel (herb) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Itasca County, MN?

Itasca County, Minnesota is in USDA Hardiness Zone 4a. The average last spring frost is May 10 and first fall frost is October 1.

When should I plant Fennel (herb) in Itasca County, MN?

In Itasca County, MN, plant Fennel (herb) after the last frost (around May 10) and before the first frost (around October 1). Best results when soil holds above 50°F.

What growing zone is Itasca County, MN for Fennel (herb)?

Itasca County sits in USDA Zone 4a. Fennel (herb) grows reliably in zones 4a through 10b, so it's a good fit here.

Can Fennel (herb) grow in Itasca County's climate?

Yes — Fennel (herb) grows well in Itasca County's temperate climate. Itasca County averages a 144-day frost-free season, with last frost around May 10 and first frost around October 1.

🌱

Your Itasca County Garden Planner — Free

A 22-page printable planner built for Itasca County (Zone 4a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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

Sources & credits

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