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When to plant Fennel (herb) in Jefferson County, FL

Plant Fennel (herb) in Jefferson County from February 16 to March 9 in spring. Jefferson County sits in USDA Zone 9a, with last frost around March 9 and first frost on November 21. A second sowing from September 26 to October 10 extends the harvest into fall.

When to Plant Fennel (herb) in Jefferson County, FL

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.

Jefferson County, Florida is in USDA Zone 9a. The average last spring frost is March 9 and the first fall frost is November 21, giving you a growing season of approximately 257 days.

At an elevation of 105 feet, Jefferson County receives approximately 56 inches of rainfall annually with predominantly sand soil. Summer highs average 95°F, so Fennel (herb) may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Fennel (herb) will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Fennel (herb) root diseases.

Jefferson County, FL (Zone 9a) Long season
257 days
Last Spring Frost March 9
257 growing days
First Fall Frost November 21

Jefferson County Soil Profile

Soil Type

Sand

Soil pH

5.2-5.9

Drainage

Well Drained

Monthly Watering Guide for Fennel (herb)

Fennel (herb) needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Fennel (herb) Needs Rainfall You Supplement Action
Jan 3" 0" ❄️ Dormant
Feb 2.9" 0" ❄️ Dormant
Mar 4.3" 3.2" 1.1" 💧 Light watering
Apr 4.3" 2.4" 1.9" 💧 Light watering
May 4.3" 3.8" 0.5" 💧 Light watering
Jun 4.3" 7.8" 0" ✅ Rainfall sufficient
Jul 4.3" 8.9" 0" ✅ Rainfall sufficient
Aug 4.3" 7.4" 0" ✅ Rainfall sufficient
Sep 4.3" 6.4" 0" ✅ Rainfall sufficient
Oct 4.3" 5" 0" ✅ Rainfall sufficient
Nov 4.3" 2.5" 1.8" 💧 Light watering
Dec 2.7" 0" ❄️ Dormant

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

Fennel (herb) Planting Timeline — Jefferson County, FL

Fennel (herb) Planting Calendar

Activity When Date Range
Start Indoors February 9 Feb 9 – Feb 23
Transplant Outdoors March 2 Mar 2 – Mar 16
Direct Sow February 16 Feb 16 – Mar 9
Harvest May 4 May 4 – Jul 13
Fall Sowing September 26 Sep 26 – Oct 10

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

Month-by-Month Timeline

MonthActivities
January
February Start Indoors Direct Sow
March Transplant Outdoors Direct Sow
April
May Harvest
June Harvest
July Harvest
August
September Fall Sowing
October Fall Sowing
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 9a

📆 Growing Season

257 days in Jefferson County

Growing Tips for Jefferson 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 Jefferson County, FL?

Jefferson County is in Zone 9a with an average last frost of March 9. Plan your Fennel (herb) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jefferson County, FL?

Jefferson County, Florida is in USDA Hardiness Zone 9a. The average last spring frost is March 9 and first fall frost is November 21.

When should I plant Fennel (herb) in Jefferson County, FL?

In Jefferson County, FL, plant Fennel (herb) after the last frost (around March 9) and before the first frost (around November 21). Best results when soil holds above 50°F.

What growing zone is Jefferson County, FL for Fennel (herb)?

Jefferson County sits in USDA Zone 9a. Fennel (herb) grows reliably in zones 4a through 10b, so it's a good fit here.

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

Yes — Fennel (herb) grows well in Jefferson County's temperate climate. Jefferson County averages a 257-day frost-free season, with last frost around March 9 and first frost around November 21.

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Your Jefferson County Garden Planner — Free

A 22-page printable planner built for Jefferson County (Zone 9a). 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 Jefferson County, FL. Local conditions may vary. Last updated: June 2026.

Sources & credits

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