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When to Plant Fennel in USDA Zone 10b

Zone 10b Zone 10b June

Your June game plan for Zone 10b

A quick June briefing for Zone 10b gardeners — what's urgent, what's next, and what can wait.

Avg. last frost February 13
Avg. first frost November 27
  1. Harvest fennel as they ripen

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

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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 10b, 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 10b Year-round
365 days
Last Spring Frost No frost
365 growing days
First Fall Frost No frost

Fennel Planting Timeline — Zone 10b

Where Is USDA Zone 10b?

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

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 10b Planting Calendar PDF

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

35°F to 40°F average annual minimum

Growing Season

365 days (Zone 10b average)

Planting Specifications

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

Succession Planting Fennel in Zone 10b

7
successive plantings in Zone 10b's ~365-day season

Sow every 6.9 weeks for continuous harvest throughout the season.

Growing Tips for Fennel in Zone 10b

Zone 10b offers a long growing season (~365 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
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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.

🌱
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 10b?

In Zone 10b, 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 10b?

Yes, Fennel can grow well in Zone 10b, hardy in USDA zones 4a through 10b. Zone 10b 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 10b?

In Zone 10b, 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 10b?

The average last spring frost in Zone 10b 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.

🌱

Your Zone 10b Garden Planner — Free

A 22-page printable planner tailored to Zone 10b. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.

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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: June 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.