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When to plant Fennel in Leon County, FL

For Fennel in Leon County, the safe spring window opens around March 11 and closes around April 1. Last expected frost is March 11, first fall frost November 21, giving a 255-day growing season.

When to Plant Fennel in Leon County, FL

Leon County, Florida Zone 9a July

Your July game plan for Leon County, Florida

Your Leon County, Florida garden is entering a new phase. Here's what's on the schedule for July and why each task matters now.

Avg. last frost March 11
Avg. first frost November 21
Soil temp (4") 90°F
Watering Low
Pest pressure High
Daylight 13.8 hrs
  1. Collect fennel at their peak

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

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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.

Leon County, Florida is in USDA Zone 9a. The average last spring frost is March 11 and the first fall frost is November 21, giving you a growing season of approximately 255 days.

At an elevation of 250 feet, Leon County receives approximately 53.9 inches of rainfall annually with predominantly sand soil. Summer highs average 95°F, so Fennel may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Fennel will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Fennel root diseases.

Leon County, FL (Zone 9a) Long season
255 days
Last Spring Frost March 11
255 growing days
First Fall Frost November 21

Leon County Soil Profile

Soil Type

Sand

Soil pH

4.8-5.7

Drainage

Well Drained

Fennel Planting Risk Windows

Early Start (70% safe) ✓ Fits season (141 days to spare)
Start indoors: Jan 20 Transplant: Mar 10 🍅 Harvest: May 12 – Jun 23
Recommended (50%) ✓ Fits season (143 days to spare)
Start indoors: Jan 28 Transplant: Mar 18 🍅 Harvest: May 20 – Jul 1
Safe Start (90%) ✓ Fits season (140 days to spare)
Start indoors: Feb 21 Transplant: Apr 11 🍅 Harvest: Jun 13 – Jul 25

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 Leon County

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

Soil pH

Your soil pH (4.8–5.7) is more acidic than Fennel prefers (5.5–7.0). Add garden lime to raise pH.

Soil Texture

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

Drainage

Drainage is adequate for Fennel.

Organic Matter

Organic matter is low (1.3%). Add 2-3 inches of compost before planting Fennel.

How to Plant Fennel

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

Succession Planting Fennel

5
successive plantings in your 255-day season

Sow every 6.9 weeks. Last sowing by Aug 23 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

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 2.2" 0" ❄️ Dormant
Feb 3.3" 0" ❄️ Dormant
Mar 2.6" 3" 0" ✅ Rainfall sufficient
Apr 2.6" 2.4" 0.2" 💧 Light watering
May 2.6" 4.1" 0" ✅ Rainfall sufficient
Jun 2.6" 7.2" 0" ✅ Rainfall sufficient
Jul 2.6" 7.6" 0" ✅ Rainfall sufficient
Aug 2.6" 7.5" 0" ✅ Rainfall sufficient
Sep 2.6" 6.9" 0" ✅ Rainfall sufficient
Oct 2.6" 5.2" 0" ✅ Rainfall sufficient
Nov 2.6" 2.1" 0.5" 💧 Light watering
Dec 2.6" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Leon 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 ~1,594 GDD — county provides 5,418 GDD Excellent fit

Fennel Planting Timeline — Leon County, FL

Fennel Planting Calendar

Activity When Date Range
Start Indoors January 28 Jan 28 – Feb 11
Transplant Outdoors March 18 Mar 18 – Apr 1
Direct Sow March 11 Mar 11 – Apr 1
Harvest May 20 May 20 – Jul 1

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

Month-by-Month Timeline

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

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: too_acidic

🗺️ USDA Zone

Zone 9a

📆 Growing Season

255 days in Leon County

Growing Tips for Fennel in Leon County

Direct sow Fennel outdoors after March 11 in Leon County when soil has warmed and frost danger has passed.

Sandy soil in Leon County dries quickly — mulch Fennel with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

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 Leon County, FL?

Leon County is in Zone 9a with an average last frost of March 11. Plan your Fennel planting based on this frost date — see the calendar above for exact timing.

What planting zone is Leon County, FL?

Leon County, Florida is in USDA Hardiness Zone 9a. The average last spring frost is March 11 and first fall frost is November 21.

When should I plant Fennel in Leon County, FL?

In Leon County, FL, plant Fennel after the last frost (around March 11) and before the first frost (around November 21). Best results when soil holds above 50°F.

What growing zone is Leon County, FL for Fennel?

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

Can Fennel grow in Leon County's climate?

Yes — Fennel grows well in Leon County's temperate climate. Leon County averages a 255-day frost-free season, with last frost around March 11 and first frost around November 21.

🌱

Your Leon County Garden Planner — Free

A 22-page printable planner built for Leon 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 Leon County, FL. Local conditions may vary. Last updated: July 2026.

Sources & credits

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