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When to Plant Fennel (herb) in USDA Zone 10a

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.

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 (herb) 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 (herb) planting schedule for that location.

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

Fennel (herb) Planting Calendar — Zone 10a

Activity When Date Range
Start Indoors December 4 Dec 4 – Dec 18
Transplant Outdoors December 25 Dec 25 – Jan 8
Direct Sow December 11 Dec 11 – Jan 1
Fall Sowing November 5 Nov 5 – Nov 19
Harvest February 26 Feb 26 – May 7

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

Month-by-Month Timeline

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

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

Growing Tips for Zone 10a

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

Level Up Your Garden

Saving Fennel (herb) Seeds

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Self-Watering Planters $15-40

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Frequently Asked Questions

When should I plant Fennel (herb) in Zone 10a?

In Zone 10a, plan your Fennel (herb) planting around the average last frost date of January 1. Start seeds indoors around December 4. Direct sow outdoors around December 11. Transplant seedlings around December 25.

Can Fennel (herb) grow in Zone 10a?

Yes, Fennel (herb) 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 (herb) (60-90 days to maturity).

When can I harvest Fennel (herb) in Zone 10a?

In Zone 10a, expect to harvest Fennel (herb) from February 26 – May 7. Fennel (herb) 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 (herb)?

Good companion plants for Fennel (herb) 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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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.