Blog

When to Plant Fennel (herb) in Franklin County, TX

Franklin County, Texas Zone 8b May

What to do in May

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

Avg. last frost March 18
Avg. first frost November 11
Soil temp (4") 71°F
Watering Low
Pest pressure High
Daylight 13.7 hrs
  1. Harvest fennel (herb) as they ripen

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

A few tasks this May that'll pay off in June
  • First harvests: fennel (herb)

Instant PDF download. No spam, unsubscribe any time.

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.

Franklin County, Texas is in USDA Zone 8b. The average last spring frost is March 18 and the first fall frost is November 11, giving you a growing season of approximately 238 days.

At an elevation of 324 feet, Franklin County receives approximately 60 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 97°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.

Franklin County, TX (Zone 8b) Long season
238 days
Last Spring Frost March 18
238 growing days
First Fall Frost November 11

Franklin County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.4-6.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (113 days to spare)
Start indoors: Feb 1 Transplant: Mar 1 🍅 Harvest: May 3 – Jul 12
Recommended (50%) ✓ Fits season (112 days to spare)
Start indoors: Feb 11 Transplant: Mar 11 🍅 Harvest: May 13 – Jul 22
Safe Start (90%) ✓ Fits season (107 days to spare)
Start indoors: Mar 4 Transplant: Apr 1 🍅 Harvest: Jun 3 – Aug 12

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 Franklin County

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

Soil pH

Your soil pH (5.4–6.3) overlaps with Fennel (herb)'s range (5.5–7.0), though not a perfect match.

Soil Texture

Sandy soil in Franklin 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 moderate (2.0%). Annual compost additions will help 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)

4
successive plantings in your 238-day season

Sow every 6.9 weeks. Last sowing by Aug 13 to harvest before frost.

For a dedicated fall crop, sow by Sep 02.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 511 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 1.5" 0" ❄️ Dormant
Feb 1.9" 0" ❄️ Dormant
Mar 4.3" 4.1" 0.2" 💧 Light watering
Apr 4.3" 5.6" 0" ✅ Rainfall sufficient
May 4.3" 7.9" 0" ✅ Rainfall sufficient
Jun 4.3" 9.9" 0" ✅ Rainfall sufficient
Jul 4.3" 8.3" 0" ✅ Rainfall sufficient
Aug 4.3" 7.1" 0" ✅ Rainfall sufficient
Sep 4.3" 6" 0" ✅ Rainfall sufficient
Oct 4.3" 3.9" 0.4" 💧 Light watering
Nov 4.3" 2.3" 2" 💧 Light watering
Dec 1.6" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Franklin County). Supplement amounts are based on average rainfall — 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" — 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 (herb) needs ~1,706 GDD — county provides 5,414 GDD Excellent fit

Fennel (herb) Planting Timeline — Franklin County, TX

Fennel (herb) Planting Calendar

Activity When Date Range
Start Indoors February 11 Feb 11 – Feb 25
Transplant Outdoors March 11 Mar 11 – Mar 25
Direct Sow March 4 Mar 4 – Mar 25
Harvest May 13 May 13 – Jul 22
Fall Sowing September 2 Sep 2 – Sep 16

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 5.5–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 8b

📆 Growing Season

238 days in Franklin County

Growing Tips for Fennel (herb) in Franklin County

Direct sow Fennel (herb) outdoors after March 18 in Franklin County when soil has warmed and frost danger has passed.

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

With summer highs reaching 97°F in Franklin County, provide afternoon shade for Fennel (herb) and water deeply in the morning.

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 Franklin County, TX?

Franklin County is in Zone 8b with an average last frost of March 18. Plan your Fennel (herb) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Franklin County, TX?

Franklin County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 18 and first fall frost is November 11.

🌱

Your Franklin County Garden Planner — Free

A 24-page printable planner built for Franklin County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Franklin County, TX. Local conditions may vary. Last updated: May 2026.

Sources & credits

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