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When to Plant Fennel in Donley 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.

Donley County, Texas is in USDA Zone 7a. The average last spring frost is April 7 and the first fall frost is October 31, giving you a growing season of approximately 207 days.

At an elevation of 4,196 feet, Donley County receives approximately 57 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 100ยฐF, so Fennel may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring โ€” great for early planting โ€” 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.

Donley County, TX (Zone 7a) Long season
207 days
Last Spring Frost April 7
207 growing days
First Fall Frost October 31

Donley County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.8-8.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (91 days to spare)
Start indoors: Feb 8 Transplant: Apr 12 🍅 Harvest: Jun 14 – Jul 26
Recommended (50%) ✓ Fits season (88 days to spare)
Start indoors: Feb 17 Transplant: Apr 21 🍅 Harvest: Jun 23 – Aug 4
Safe Start (90%) ✓ Fits season (91 days to spare)
Start indoors: Mar 2 Transplant: May 4 🍅 Harvest: Jul 6 – Aug 17

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Donley County

How your county's soil matches Fennel's growing requirements.

Soil pH

Your soil pH (7.8โ€“8.2) is more alkaline than Fennel prefers (5.5โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Donley County warms quickly in spring but drains fast. Fennel will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is low (1.0%). Add 2-3 inches of compost before planting Fennel.

How to Plant Fennel

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Succession Planting Fennel

4
successive plantings in your 207-day season

Sow every 6.9 weeks. Last sowing by Aug 02 to harvest before frost.

Plant Water Budget

Plant needs
0.6″/week
Rainfall provides
1.2″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Fennel

Fennel needs approximately 0.6 inches of water per week (2.6" per month). Here's how your county's rainfall compares month by month.

Month Fennel Needs Rainfall You Supplement Action
Jan โ€” 4.3" 0" โ„๏ธ Dormant
Feb โ€” 2.9" 0" โ„๏ธ Dormant
Mar โ€” 3.2" 0" โ„๏ธ Dormant
Apr 2.6" 1.9" 0.7" ๐Ÿ’ง Light watering
May 2.6" 1.3" 1.3" ๐Ÿšฟ Regular watering
Jun 2.6" 2.1" 0.5" ๐Ÿ’ง Light watering
Jul 2.6" 10.9" 0" โœ… Rainfall sufficient
Aug 2.6" 11.1" 0" โœ… Rainfall sufficient
Sep 2.6" 8.3" 0" โœ… Rainfall sufficient
Oct 2.6" 4.5" 0" โœ… Rainfall sufficient
Nov โ€” 3.1" 0" โ„๏ธ Dormant
Dec โ€” 3.3" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Donley County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Fennel Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" โ€” every day above 50ยฐF deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Fennel needs ~1,875 GDD — county provides 5,175 GDD Excellent fit

Fennel Planting Timeline โ€” Donley County, TX

Fennel Planting Calendar

Activity When Date Range
Start Indoors February 17 Feb 17 โ€“ Mar 3
Transplant Outdoors April 21 Apr 21 โ€“ May 5
Direct Sow April 14 Apr 14 โ€“ May 5
Harvest June 23 Jun 23 โ€“ Aug 4

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.6"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

60โ€“90 days

๐Ÿงช Soil pH

Needs 5.5โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

207 days in Donley County

Growing Tips for Fennel in Donley County

Direct sow Fennel outdoors after April 07 in Donley County when soil has warmed and frost danger has passed.

Sandy soil in Donley County dries quickly โ€” mulch Fennel with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

With summer highs reaching 100ยฐF in Donley County, provide afternoon shade for Fennel and water deeply in the morning.

Common pests for Fennel in this region include carrot rust fly and parsleyworm. Use row covers early in the season and inspect plants weekly.

General growing tips

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 Donley County, TX?

Donley County is in Zone 7a with an average last frost of April 7. Plan your Fennel planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Donley County, TX?

Donley County, Texas is in USDA Hardiness Zone 7a. The average last spring frost is April 7 and first fall frost is October 31.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Donley County gardeners in Zone 7a 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 Donley County, TX. Local conditions may vary. Last updated: April 2026.