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When to Plant Fennel (herb) in Hamilton 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.

Hamilton County, Florida is in USDA Zone 8b. The average last spring frost is March 4 and the first fall frost is November 26, giving you a growing season of approximately 267 days.

At an elevation of 279 feet, Hamilton County receives approximately 61.2 inches of rainfall annually with predominantly sand soil. Summer highs average 93ยฐF, providing good warmth for Fennel (herb) during the growing season. Sandy soil warms quickly in spring โ€” great for early planting โ€” 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.

Hamilton County, FL (Zone 8b) Long season
267 days
Last Spring Frost March 4
267 growing days
First Fall Frost November 26

Hamilton County Soil Profile

Soil Type

Sand

Soil pH

5.2-5.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (144 days to spare)
Start indoors: Jan 15 Transplant: Feb 12 🍅 Harvest: Apr 16 – Jun 25
Recommended (50%) ✓ Fits season (141 days to spare)
Start indoors: Jan 28 Transplant: Feb 25 🍅 Harvest: Apr 29 – Jul 8
Safe Start (90%) ✓ Fits season (145 days to spare)
Start indoors: Feb 17 Transplant: Mar 17 🍅 Harvest: May 19 – Jul 28

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 Hamilton County

How your county's soil matches Fennel (herb)'s growing requirements.

Soil pH

Your soil pH (5.2โ€“5.7) is more acidic than Fennel (herb) prefers (5.5โ€“7.0). Add garden lime to raise pH.

Soil Texture

Sandy soil in Hamilton County warms quickly in spring but drains fast. Fennel (herb) will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Fennel (herb).

Organic Matter

Organic matter is low (1.4%). Add 2-3 inches of compost before planting Fennel (herb).

How to Plant Fennel (herb)

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

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Fennel (herb)

5
successive plantings in your 267-day season

Sow every 6.9 weeks. Last sowing by Aug 28 to harvest before frost.

For a dedicated fall crop, sow by Sep 17.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 802 gal / 100 sq ft

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 โ€” 3.2" 0" โ„๏ธ Dormant
Feb โ€” 3.1" 0" โ„๏ธ Dormant
Mar 4.3" 3.3" 1" ๐Ÿ’ง Light watering
Apr 4.3" 2.4" 1.9" ๐Ÿ’ง Light watering
May 4.3" 3.4" 0.9" ๐Ÿ’ง Light watering
Jun 4.3" 9.3" 0" โœ… Rainfall sufficient
Jul 4.3" 8.8" 0" โœ… Rainfall sufficient
Aug 4.3" 9.2" 0" โœ… Rainfall sufficient
Sep 4.3" 8.5" 0" โœ… Rainfall sufficient
Oct 4.3" 5" 0" โœ… Rainfall sufficient
Nov 4.3" 2.7" 1.6" ๐Ÿ’ง Light watering
Dec โ€” 2.4" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Hamilton County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Fennel (herb) 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" โ€” every day above 50ยฐF 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 (herb) needs ~1,481 GDD — county provides 5,273 GDD Excellent fit

Fennel (herb) Planting Timeline โ€” Hamilton County, FL

Fennel (herb) Planting Calendar

Activity When Date Range
Start Indoors January 28 Jan 28 โ€“ Feb 11
Transplant Outdoors February 25 Feb 25 โ€“ Mar 11
Direct Sow February 18 Feb 18 โ€“ Mar 11
Harvest April 29 Apr 29 โ€“ Jul 8
Fall Sowing September 17 Sep 17 โ€“ Oct 1

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

60โ€“90 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: too_acidic

๐Ÿ—บ๏ธ USDA Zone

Zone 8b

๐Ÿ“† Growing Season

267 days in Hamilton County

Growing Tips for Fennel (herb) in Hamilton County

Direct sow Fennel (herb) outdoors after March 04 in Hamilton County when soil has warmed and frost danger has passed.

Sandy soil in Hamilton County dries quickly โ€” mulch Fennel (herb) with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

Common pests for Fennel (herb) 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 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 Hamilton County, FL?

Hamilton County is in Zone 8b with an average last frost of March 4. Plan your Fennel (herb) planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Hamilton County, FL?

Hamilton County, Florida is in USDA Hardiness Zone 8b. The average last spring frost is March 4 and first fall frost is November 26.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Hamilton County gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.

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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 Hamilton County, FL. Local conditions may vary. Last updated: April 2026.