When to Plant Fennel in Oklahoma County, OK
Top priorities for Oklahoma County, Oklahoma gardeners in May
Here's what deserves your attention in Oklahoma County, Oklahoma this month. Everything below is tailored to Zone 7b and timed around your local frost dates.
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Start fennel 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.
A few tasks this May that'll pay off in June
- First harvests: fennel
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.
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 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's growing requirements.
Soil pH
Your soil pH (6.5–7.6) is more alkaline than Fennel 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 — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.4%). Annual compost additions will help Fennel.
How to Plant Fennel
Succession Planting Fennel
Sow every 6.9 weeks. Last sowing by Aug 07 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — 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 | — | 0.7" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 1.8" | 0" | ❄️ Dormant |
| Apr | 2.6" | 2.9" | 0" | ✅ Rainfall sufficient |
| May | 2.6" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jun | 2.6" | 3.9" | 0" | ✅ Rainfall sufficient |
| Jul | 2.6" | 3.6" | 0" | ✅ Rainfall sufficient |
| Aug | 2.6" | 3.1" | 0" | ✅ Rainfall sufficient |
| Sep | 2.6" | 2.5" | 0.1" | 💧 Light watering |
| Oct | 2.6" | 1.4" | 1.2" | 💧 Light watering |
| Nov | 2.6" | 0.9" | 1.7" | 🚿 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 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 Planting Timeline — Oklahoma County, OK
Fennel Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 12 | Feb 12 – Feb 26 |
| Transplant Outdoors | April 16 | Apr 16 – Apr 30 |
| Direct Sow | April 9 | Apr 9 – Apr 30 |
| Harvest | June 18 | Jun 18 – Jul 30 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | — |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.6"/week · Only during dry spells
📅 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 in Oklahoma County
Direct sow Fennel outdoors after April 02 in Oklahoma County when soil has warmed and frost danger has passed.
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
Check more plant combinations with our Companion Planting Checker →
Fennel in Other Locations
Frequently Asked Questions
When should I plant Fennel in Oklahoma County, OK?
Oklahoma County is in Zone 7b with an average last frost of April 2. Plan your Fennel 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.