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When to Plant Fennel in USDA Zone 6b

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.

In Zone 6b, the average last spring frost is around April 3 and the first fall frost is around October 25, giving you a growing season of approximately 205 days.

Zone 6b Long season
205 days
Last Spring Frost April 3
205 growing days
First Fall Frost October 25

Fennel Planting Timeline — Zone 6b

Where Is USDA Zone 6b?

The map below highlights the states that contain Zone 6b. Click any state to see the Fennel planting schedule for that location.

Prints a clean, ink-friendly version without maps or navigation.

Fennel Planting Calendar — Zone 6b

Activity When Date Range
Start Indoors February 6 Feb 6 – Feb 20
Transplant Outdoors April 17 Apr 17 – May 1
Direct Sow April 10 Apr 10 – May 1
Harvest June 19 Jun 19 – Jul 31

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

Month-by-Month Timeline

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

Free Zone 6b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 6b with start dates, transplant windows, and harvest times.

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Growing Conditions

Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

Days to Maturity

60–90 days

Soil pH

5.5 – 7

Zone Temperature Range

-5°F to 0°F average annual minimum

Growing Season

205 days (Zone 6b average)

Planting Specifications

Planting Depth1 inches
Plant Spacing15 inches apart
Row Spacing24 inches between rows

Succession Planting Fennel in Zone 6b

4
successive plantings in Zone 6b's ~205-day season

Sow every 6.9 weeks for continuous harvest throughout the season.

Growing Tips for Fennel in Zone 6b

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

Level Up Your Garden

Saving Fennel Seeds

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Seed Starting Trays $8-20

Start seeds indoors with reusable cell trays and humidity domes.

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Soil Test Kit $12-25

Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.

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Garden Plant Markers $6-12

Keep your garden organized with durable, weather-resistant plant labels.

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Frequently Asked Questions

When should I plant Fennel in Zone 6b?

In Zone 6b, plan your Fennel planting around the average last frost date of April 3. Start seeds indoors around February 6. Direct sow outdoors around April 10. Transplant seedlings around April 17.

Can Fennel grow in Zone 6b?

Yes, Fennel can grow well in Zone 6b, hardy in USDA zones 4a through 10b. Zone 6b has a growing season of approximately 205 days, which is sufficient for Fennel (60-90 days to maturity).

When can I harvest Fennel in Zone 6b?

In Zone 6b, expect to harvest Fennel from June 19 – July 31. Fennel takes 60-90 days from planting to harvest.

What is the last frost date for Zone 6b?

The average last spring frost in Zone 6b is around April 3, and the first fall frost is around October 25. This gives a growing season of approximately 205 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Fennel?

Good companion plants for Fennel include Peas, Lettuce. These companions can help with pest control, pollination, and nutrient sharing.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner — organize your planting dates for Zone 6b, track your crops, and plan your garden season from seed to harvest.

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Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — local conditions may vary. Last updated: April 2026.