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When to Plant Fennel in USDA Zone 9b

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 9b, the average last spring frost is around January 25 and the first fall frost is around December 20, giving you a growing season of approximately 329 days.

Zone 9b Year-round
329 days
Last Spring Frost January 25
329 growing days
First Fall Frost December 20

Fennel Planting Timeline — Zone 9b

Where Is USDA Zone 9b?

The map below highlights the states that contain Zone 9b. 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 9b

Activity When Date Range
Start Indoors December 14 Dec 14 – Dec 28
Transplant Outdoors February 1 Feb 1 – Feb 15
Direct Sow January 25 Jan 25 – Feb 15
Harvest April 5 Apr 5 – May 17

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

Month-by-Month Timeline

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

Free Zone 9b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 9b 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

25°F to 30°F average annual minimum

Growing Season

329 days (Zone 9b average)

Planting Specifications

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

Succession Planting Fennel in Zone 9b

6
successive plantings in Zone 9b's ~329-day season

Sow every 6.9 weeks for continuous harvest throughout the season.

Growing Tips for Fennel in Zone 9b

Zone 9b offers a long growing season (~329 days). You can plant Fennel earlier and may get multiple harvests.

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

Recommended for Your Garden

☀️
Garden Shade Cloth $15-35

Reduce heat stress and sun scorch in hot climates with UV-stabilized shade cloth.

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Seed Starting Trays $8-20

Start seeds indoors with reusable cell trays and humidity domes.

🧪
Soil Test Kit $12-25

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

Related Plants

Frequently Asked Questions

When should I plant Fennel in Zone 9b?

In Zone 9b, plan your Fennel planting around the average last frost date of January 25. Start seeds indoors around December 14. Direct sow outdoors around January 25. Transplant seedlings around February 1.

Can Fennel grow in Zone 9b?

Yes, Fennel can grow well in Zone 9b, hardy in USDA zones 4a through 10b. Zone 9b has a growing season of approximately 329 days, which is sufficient for Fennel (60-90 days to maturity).

When can I harvest Fennel in Zone 9b?

In Zone 9b, expect to harvest Fennel from April 5 – May 17. Fennel takes 60-90 days from planting to harvest.

What is the last frost date for Zone 9b?

The average last spring frost in Zone 9b is around January 25, and the first fall frost is around December 20. This gives a growing season of approximately 329 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 9b, 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.