Fennel Planting Guide

May

May fennel essentials

Whether you're sowing, transplanting, or harvesting, fennel needs the right timing. Check your zone below for exact dates.

Sun full sun

Water moderate

Days to harvest 60–90

Plant depth 1″

Spacing 15″

How to water fennel
Consistent moisture matters more than volume for fennel. Little and often beats occasional drenching.
Where to put fennel
South-facing beds are ideal for fennel. Shade from nearby trees or fences costs real production.
Check your local forecast before planting
Your zone determines the exact week to plant fennel. Pick your county below and we'll line everything up against your frost dates.

Show me fennel timing for my zone →

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.

Foeniculum vulgare var. azoricum · Vegetable · Apiaceae family · 60–90 days to maturity

Get Your Personalized Fennel Planting Dates

Enter your ZIP code to see exact planting dates, soil compatibility, and growing tips specific to your county.

Where Can You Grow Fennel?

Zone Compatibility for Fennel Zones 4a – 10b

1a 1b 2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a 11b 12a 12b 13a 13b

Ideal (data available) Suitable Marginal Not recommended

Planting Dates by Zone

Zone	Start Indoors	Direct Sow	Transplant	Harvest
Zone 4a	Mar 4	May 20	May 27	Jul 29 – Sep 9
Zone 4b	Feb 27	May 15	May 22	Jul 24 – Sep 4
Zone 5a	Feb 28	May 2	May 9	Jul 11 – Aug 22
Zone 5b	Feb 21	Apr 25	May 2	Jul 4 – Aug 15
Zone 6a	Feb 13	Apr 17	Apr 24	Jun 26 – Aug 7
Zone 6b	Feb 6	Apr 10	Apr 17	Jun 19 – Jul 31
Zone 7a	Feb 4	Apr 1	Apr 8	Jun 10 – Jul 22
Zone 7b	Jan 28	Mar 25	Apr 1	Jun 3 – Jul 15
Zone 8a	Jan 18	Mar 15	Mar 22	May 24 – Jul 5
Zone 8b	Jan 7	Mar 4	Mar 11	May 13 – Jun 24
Zone 9a	Dec 30	Feb 10	Feb 17	Apr 21 – Jun 2
Zone 9b	Dec 14	Jan 25	Feb 1	Apr 5 – May 17
Zone 10a	Nov 20	Jan 1	Jan 8	Mar 12 – Apr 23
Zone 10b	Nov 20	Jan 1	Jan 8	Mar 12 – Apr 23

How to Plant Fennel

Planting Depth

15"

Between Plants

24"

Between Rows

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

Water when the top inch of soil feels dry. Consistent moisture produces the best results.

🧪 Soil pH

5.5 – 7

Prefers neutral to slightly acidic soil — ideal for most garden beds.

🗺️ Hardiness Zones

Zone 4a – 10b

📅 Days to Maturity

60–90 days

Quick-growing crop. Multiple plantings per season are possible.

👪 Plant Family

Apiaceae

Rotate with other families yearly to prevent soil-borne diseases. Don't plant in the same spot where Apiaceae family crops grew last year.

Succession Planting Fennel

Fennel matures in just 60–90 days, making it ideal for succession planting. In a typical 180-day growing season, you can get up to 3 successive plantings by sowing every 6.9 weeks.

Your actual succession count depends on your local frost dates. Enter your ZIP code to get personalized succession planting dates for your area.

Companion Planting for Fennel

✅ Good Companions

Peas Lettuce

❌ Keep Away From

Tomatoes Peppers Beans

Check more combinations with our Companion Planting Checker →

Growing Tips for Fennel

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.

Saving Fennel Seeds

Recommended for Your Garden

🌱

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.

🏷️

Garden Plant Markers $6-12

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

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Seed Saving & Storage Guide

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Most saved seeds go bad before next season. This shows exactly when to pick, how to dry, and where to store seeds from 200 plants so yours don't.

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Fennel by State

Frequently Asked Questions

How long does it take to grow Fennel?

Fennel (Foeniculum vulgare var. azoricum) takes 60 to 90 days from planting to harvest. Exact timing depends on your variety, growing conditions, and USDA zone.

What zones can Fennel grow in?

Fennel can be grown in USDA zones 4a through 10b. Use the planting calendar above to find the exact dates for your zone.

How much sun does Fennel need?

Growing Fennel requires Full Sun (6-8+ hours), Moderate — regular watering, and soil pH of 5.5 to 7.