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When to Plant Fennel in King County, TX

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.

King County, Texas is in USDA Zone 7b. The average last spring frost is March 31 and the first fall frost is November 7, giving you a growing season of approximately 221 days.

At an elevation of 3,170 feet, King County receives approximately 60.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 99Β°F, so Fennel may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring β€” great for early planting β€” but Fennel will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Fennel root diseases.

King County, TX (Zone 7b) Long season
221 days
Last Spring Frost March 31
221 growing days
First Fall Frost November 7

King County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.8-8.4

Drainage

Well Drained

Monthly Watering Guide for Fennel

Fennel needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Fennel Needs Rainfall You Supplement Action
Jan β€” 4.7" 0" ❄️ Dormant
Feb β€” 3.2" 0" ❄️ Dormant
Mar 4.3" 3.9" 0.4" πŸ’§ Light watering
Apr 4.3" 2.3" 2" πŸ’§ Light watering
May 4.3" 1.5" 2.8" 🚿 Regular watering
Jun 4.3" 2.2" 2.1" πŸ’§ Light watering
Jul 4.3" 10.4" 0" βœ… Rainfall sufficient
Aug 4.3" 11.5" 0" βœ… Rainfall sufficient
Sep 4.3" 8.1" 0" βœ… Rainfall sufficient
Oct 4.3" 5.7" 0" βœ… Rainfall sufficient
Nov 4.3" 3" 1.3" πŸ’§ Light watering
Dec β€” 3.7" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in King County). Supplement amounts are based on average rainfall β€” actual needs vary with temperature, soil, and mulching.

Fennel Planting Timeline β€” King County, TX

Fennel Planting Calendar

Activity When Date Range
Start Indoors February 10 Feb 10 – Feb 24
Transplant Outdoors April 14 Apr 14 – Apr 28
Direct Sow April 7 Apr 7 – Apr 28
Harvest June 16 Jun 16 – Jul 28

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

Month-by-Month Timeline

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

Growing Conditions

β˜€οΈ Sun

Full Sun (6-8+ hours)

πŸ’§ Water

Moderate β€” regular watering

πŸ“… Days to Maturity

60–90 days

πŸ§ͺ Soil pH

Needs 5.5–7 Β· Your soil: N/A

πŸ—ΊοΈ USDA Zone

Zone 7b

πŸ“† Growing Season

221 days in King County

Growing Tips for King County

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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Fennel in King County, TX?

King County is in Zone 7b with an average last frost of March 31. Plan your Fennel planting based on this frost date β€” see the calendar above for exact timing.

What planting zone is King County, TX?

King County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 31 and first fall frost is November 7.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner β€” designed to help King County gardeners in Zone 7b organize planting dates, track what's growing, and never miss a planting window.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for King County, TX. Local conditions may vary. Last updated: April 2026.