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When to plant Fennel in Clinton County County,

Fennel planted in Clinton County County between May 7 and May 28 matures in 90 days — well before the October 13 first frost.

When to Plant Fennel in Clinton County, MI

Clinton County, Michigan Zone 6a June

Clinton County, Michigan gardeners: here's your June plan

We've pulled the most time-sensitive tasks for Clinton County, Michigan this June and put them front and centre. Tackle them in order.

Avg. last frost April 30
Avg. first frost October 13
Soil temp (4") 69°F
Watering Low
Pest pressure High
Daylight 15.2 hrs
  1. Fire up the seed-starting tray: fennel

    Your window is short. These crops want several weeks of indoor growth before they go outside.

Get ahead of July
  • First harvests: fennel

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Florence fennel is grown for its swollen bulb-like stem base, which has a mild anise flavor. It is crisp raw in salads and sweet when roasted or braised.

Clinton County, Michigan is in USDA Zone 6a. The average last spring frost is April 30 and the first fall frost is October 13, giving you a growing season of approximately 166 days.

At an elevation of 519 feet, Clinton County receives approximately 34.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Fennel to ensure they mature before fall.

Clinton County, MI (Zone 6a) Moderate season
166 days
Last Spring Frost April 30
166 growing days
First Fall Frost October 13
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Clinton County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.7

Drainage

Well Drained

Fennel Planting Risk Windows

Early Start (70% safe) ✓ Fits season (43 days to spare)
Start indoors: Mar 2 Transplant: May 11 🍅 Harvest: Jul 13 – Aug 24
Recommended (50%) ✓ Fits season (47 days to spare)
Start indoors: Mar 5 Transplant: May 14 🍅 Harvest: Jul 16 – Aug 27
Safe Start (90%) ✓ Fits season (43 days to spare)
Start indoors: Mar 25 Transplant: Jun 3 🍅 Harvest: Aug 5 – Sep 16

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 Clinton County

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

Soil pH

Your soil pH (5.9–6.7) is within Fennel's preferred range (5.5–7.0).

Soil Texture

The silt loam soil in Clinton County is excellent for Fennel — good drainage, moisture retention, and nutrient holding capacity.

Drainage

Drainage is adequate for Fennel.

Organic Matter

Organic matter is excellent (4.8%) — Fennel will thrive.

How to Plant Fennel

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Succession Planting Fennel

3
successive plantings in your 166-day season

Sow every 6.9 weeks. Last sowing by Jul 15 to harvest before frost.

Fennel Water Budget

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

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Fennel

Fennel needs approximately 0.6 inches of water per week (2.6" per month). Here's how your county's rainfall compares month by month.

Month Fennel Needs Rainfall You Supplement Action
Jan 1.4" 0" ❄️ Dormant
Feb 1.7" 0" ❄️ Dormant
Mar 2.4" 0" ❄️ Dormant
Apr 2.6" 2.9" 0" ✅ Rainfall sufficient
May 2.6" 3.8" 0" ✅ Rainfall sufficient
Jun 2.6" 4.1" 0" ✅ Rainfall sufficient
Jul 2.6" 3.7" 0" ✅ Rainfall sufficient
Aug 2.6" 3.9" 0" ✅ Rainfall sufficient
Sep 2.6" 3" 0" ✅ Rainfall sufficient
Oct 2.6" 2.7" 0" ✅ Rainfall sufficient
Nov 2.5" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Clinton County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Fennel 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" — every day above 50°F 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.

Fennel needs ~975 GDD — county provides 2,158 GDD Excellent fit

Fennel Planting Timeline — Clinton County, MI

Fennel Planting Calendar

Activity When Date Range
Start Indoors March 5 Mar 5 – Mar 19
Transplant Outdoors May 14 May 14 – May 28
Direct Sow May 7 May 7 – May 28
Harvest July 16 Jul 16 – Aug 27

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.6"/week · Natural rainfall sufficient

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 5.5–7 · Your soil: ideal

🗺️ USDA Zone

Zone 6a

📆 Growing Season

166 days in Clinton County

Growing Tips for Fennel in Clinton County

Direct sow Fennel outdoors after April 30 in Clinton County when soil has warmed and frost danger has passed.

Common pests for Fennel in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow in late summer for fall harvest to reduce bolting. Hill soil around bulbs as they enlarge. Harvest when bulbs are tennis-ball sized before they elongate.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Peppers
  • Beans

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Fennel in Clinton County, MI?

Clinton County is in Zone 6a with an average last frost of April 30. Plan your Fennel planting based on this frost date — see the calendar above for exact timing.

What planting zone is Clinton County, MI?

Clinton County, Michigan is in USDA Hardiness Zone 6a. The average last spring frost is April 30 and first fall frost is October 13.

When should I plant Fennel in Clinton County County, ?

In Clinton County County, , plant Fennel after the last frost (around April 30) and before the first frost (around October 13). Best results when soil holds above 50°F.

What growing zone is Clinton County County, for Fennel?

Clinton County County sits in USDA Zone 6a. Fennel grows reliably in zones 4a through 10b, so it's a good fit here.

Can Fennel grow in Clinton County County's climate?

Yes — Fennel grows well in Clinton County County's temperate climate. Clinton County County averages a 166-day frost-free season, with last frost around April 30 and first frost around October 13.

🌱

Your Clinton County Garden Planner — Free

A 22-page printable planner built for Clinton County (Zone 6a). 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 Clinton County, MI. Local conditions may vary. Last updated: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.