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When to Plant Fennel in USDA Zone 10a

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 10a, the average last spring frost is around January 1 and the first fall frost is around December 31, giving you a growing season of approximately 364 days.

Zone 10a Year-round
364 days
Last Spring Frost January 1
364 growing days
First Fall Frost December 31

Fennel Planting Timeline — Zone 10a

Where Is USDA Zone 10a?

The map below highlights the states that contain Zone 10a. 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 10a

Activity When Date Range
Start Indoors November 20 Nov 20 – Dec 4
Transplant Outdoors January 8 Jan 8 – Jan 22
Direct Sow January 1 Jan 1 – Jan 22
Harvest March 12 Mar 12 – Apr 23

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

Month-by-Month Timeline

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

Free Zone 10a Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 10a 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

30°F to 35°F average annual minimum

Growing Season

364 days (Zone 10a average)

Planting Specifications

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

Succession Planting Fennel in Zone 10a

7
successive plantings in Zone 10a's ~364-day season

Sow every 6.9 weeks for continuous harvest throughout the season.

Growing Tips for Fennel in Zone 10a

Zone 10a offers a long growing season (~364 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.

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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 10a?

In Zone 10a, plan your Fennel planting around the average last frost date of January 1. Start seeds indoors around November 20. Direct sow outdoors around January 1. Transplant seedlings around January 8.

Can Fennel grow in Zone 10a?

Yes, Fennel can grow well in Zone 10a, hardy in USDA zones 4a through 10b. Zone 10a has a growing season of approximately 364 days, which is sufficient for Fennel (60-90 days to maturity).

When can I harvest Fennel in Zone 10a?

In Zone 10a, expect to harvest Fennel from March 12 – April 23. Fennel takes 60-90 days from planting to harvest.

What is the last frost date for Zone 10a?

The average last spring frost in Zone 10a is around January 1, and the first fall frost is around December 31. This gives a growing season of approximately 364 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 10a, 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.