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When to Plant Fennel (herb) in Gloucester County, NJ

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.

Gloucester County, New Jersey is in USDA Zone 7a. The average last spring frost is April 5 and the first fall frost is November 12, giving you a growing season of approximately 221 days.

At an elevation of 735 feet, Gloucester County receives approximately 49.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 94ยฐF, providing good warmth for Fennel (herb) during the growing season.

Gloucester County, NJ (Zone 7a) Long season
221 days
Last Spring Frost April 5
221 growing days
First Fall Frost November 12

Gloucester County Soil Profile

Soil Type

Silt Loam

Soil pH

5.2-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (96 days to spare)
Start indoors: Feb 17 Transplant: Mar 17 🍅 Harvest: May 19 – Jul 28
Recommended (50%) ✓ Fits season (95 days to spare)
Start indoors: Mar 1 Transplant: Mar 29 🍅 Harvest: May 31 – Aug 9
Safe Start (90%) ✓ Fits season (95 days to spare)
Start indoors: Mar 24 Transplant: Apr 21 🍅 Harvest: Jun 23 – Sep 1

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 Gloucester County

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

Soil pH

Your soil pH (5.2โ€“6.8) overlaps with Fennel (herb)'s range (5.5โ€“7.0), though not a perfect match.

Soil Texture

The silt loam soil in Gloucester County is excellent for Fennel (herb) โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.5%). 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 221-day season

Sow every 6.9 weeks. Last sowing by Aug 14 to harvest before frost.

For a dedicated fall crop, sow by Sep 03.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 102 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€” 3.7" 0" โ„๏ธ Dormant
Feb โ€” 3" 0" โ„๏ธ Dormant
Mar โ€” 4.5" 0" โ„๏ธ Dormant
Apr 4.3" 4" 0.3" ๐Ÿ’ง Light watering
May 4.3" 4.8" 0" โœ… Rainfall sufficient
Jun 4.3" 4.3" 0" โœ… Rainfall sufficient
Jul 4.3" 5.3" 0" โœ… Rainfall sufficient
Aug 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Sep 4.3" 4.3" 0" โœ… Rainfall sufficient
Oct 4.3" 3.9" 0.4" ๐Ÿ’ง Light watering
Nov 4.3" 4.1" 0.2" ๐Ÿ’ง Light watering
Dec โ€” 3.8" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Nov in Gloucester 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 ~1,538 GDD — county provides 4,530 GDD Excellent fit

Fennel (herb) Planting Timeline โ€” Gloucester County, NJ

Fennel (herb) Planting Calendar

Activity When Date Range
Start Indoors March 1 Mar 1 โ€“ Mar 15
Transplant Outdoors March 29 Mar 29 โ€“ Apr 12
Direct Sow March 22 Mar 22 โ€“ Apr 12
Harvest May 31 May 31 โ€“ Aug 9
Fall Sowing September 3 Sep 3 โ€“ Sep 17

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

60โ€“90 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

221 days in Gloucester County

Growing Tips for Fennel (herb) in Gloucester County

Direct sow Fennel (herb) outdoors after April 05 in Gloucester County when soil has warmed and frost danger has passed.

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 Gloucester County, NJ?

Gloucester County is in Zone 7a with an average last frost of April 5. Plan your Fennel (herb) planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Gloucester County, NJ?

Gloucester County, New Jersey is in USDA Hardiness Zone 7a. The average last spring frost is April 5 and first fall frost is November 12.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Gloucester County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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