When to Plant Fennel (herb) in Oklahoma County, OK
Your May game plan for Oklahoma County, Oklahoma
Welcome to May in Zone 7b. These are the moves that will have the biggest impact on your growing season.
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Start fennel (herb) under lights
These need a head start before your last frost (April 2). Sow into cells now so you're ready to transplant in a few weeks.
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Bring in the fennel (herb)
If you can't use it all right away, check the food-preservation section of your planner.
Looking ahead to June
- First harvests: fennel (herb)
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.
Oklahoma County, Oklahoma is in USDA Zone 7b. The average last spring frost is April 2 and the first fall frost is November 5, giving you a growing season of approximately 217 days.
At an elevation of 739 feet, Oklahoma County receives approximately 26.6 inches of rainfall annually with predominantly loam soil. Summer highs average 88°F, providing good warmth for Fennel (herb) during the growing season.
Oklahoma County Soil Profile
Soil Type
Loam
Soil pH
6.5-7.6
Drainage
Well Drained
Plant Planting Risk Windows
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 Oklahoma County
How your county's soil matches Fennel (herb)'s growing requirements.
Soil pH
Your soil pH (6.5–7.6) is more alkaline than Fennel (herb) prefers (5.5–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Oklahoma County is excellent for Fennel (herb) — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.4%). Annual compost additions will help Fennel (herb).
How to Plant Fennel (herb)
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Fennel (herb)
Sow every 6.9 weeks. Last sowing by Aug 07 to harvest before frost.
For a dedicated fall crop, sow by Aug 27.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Fennel (herb)
Fennel (herb) 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 (herb) Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 0.7" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 1.8" | 0" | ❄️ Dormant |
| Apr | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| May | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Jul | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Aug | 4.3" | 3.1" | 1.2" | 💧 Light watering |
| Sep | 4.3" | 2.5" | 1.8" | 💧 Light watering |
| Oct | 4.3" | 1.4" | 2.9" | 🚿 Regular watering |
| Nov | 4.3" | 0.9" | 3.4" | 🚿 Regular watering |
| Dec | — | 0.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in Oklahoma County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Fennel (herb) 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" — every day above 50°F 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 (herb) Planting Timeline — Oklahoma County, OK
Fennel (herb) Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 26 | Feb 26 – Mar 12 |
| Transplant Outdoors | March 26 | Mar 26 – Apr 9 |
| Direct Sow | March 19 | Mar 19 – Apr 9 |
| Harvest | May 28 | May 28 – Aug 6 |
| Fall Sowing | August 27 | Aug 27 – Sep 10 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Transplant Outdoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | Fall Sowing |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 5.5–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 7b
📆 Growing Season
217 days in Oklahoma County
Growing Tips for Fennel (herb) in Oklahoma County
Direct sow Fennel (herb) outdoors after April 02 in Oklahoma County when soil has warmed and frost danger has passed.
Common pests for Fennel (herb) 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 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
Check more plant combinations with our Companion Planting Checker →
Fennel (herb) in Other Locations
Frequently Asked Questions
When should I plant Fennel (herb) in Oklahoma County, OK?
Oklahoma County is in Zone 7b with an average last frost of April 2. Plan your Fennel (herb) planting based on this frost date — see the calendar above for exact timing.
What planting zone is Oklahoma County, OK?
Oklahoma County, Oklahoma is in USDA Hardiness Zone 7b. The average last spring frost is April 2 and first fall frost is November 5.
Your Oklahoma County Garden Planner — Free
A 24-page printable planner built for Oklahoma County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.