When to Plant Fennel (herb) in Sheridan County, WY
Your May gardening checklist
Welcome to May in Zone 5a. These are the moves that will have the biggest impact on your growing season.
-
Move fennel (herb) from tray to bed
Plant tomatoes deep — bury the stem up to the first true leaves to grow extra roots. Everything else goes in at the same depth it grew in the tray.
-
Seed fennel (herb) outdoors
These tolerate cool soil, so you're not gambling by sowing now.
Coming up in June — start thinking about
- Starting indoors: 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.
Sheridan County, Wyoming is in USDA Zone 5a. The average last spring frost is May 20 and the first fall frost is September 20, giving you a growing season of approximately 123 days.
At an elevation of 5,266 feet, Sheridan County receives approximately 14.7 inches of rainfall annually with predominantly loam soil. Summer highs average 82°F, so choose short-season varieties of Fennel (herb) to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Fennel (herb) successfully. Mulch heavily to conserve soil moisture.
Sheridan County Soil Profile
Soil Type
Loam
Soil pH
6.6-7.8
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 Sheridan County
How your county's soil matches Fennel (herb)'s growing requirements.
Soil pH
Your soil pH (6.6–7.8) 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 Sheridan County is excellent for Fennel (herb) — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Fennel (herb).
Organic Matter
Organic matter is moderate (2.6%). 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 Jun 22 to harvest before frost.
For a dedicated fall crop, sow by Jul 12.
Plant Water Budget
Water stress score is 8/10 — 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 | — | 1.1" | 0" | ❄️ Dormant |
| Feb | — | 0.9" | 0" | ❄️ Dormant |
| Mar | — | 1.2" | 0" | ❄️ Dormant |
| Apr | — | 1.4" | 0" | ❄️ Dormant |
| May | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Jun | 4.3" | 1" | 3.3" | 🚿 Regular watering |
| Jul | 4.3" | 1.1" | 3.2" | 🚿 Regular watering |
| Aug | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Sep | 4.3" | 1.1" | 3.2" | 🚿 Regular watering |
| Oct | — | 1.2" | 0" | ❄️ Dormant |
| Nov | — | 1.1" | 0" | ❄️ Dormant |
| Dec | — | 0.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Sheridan 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 — Sheridan County, WY
Fennel (herb) Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 15 | Apr 15 – Apr 29 |
| Transplant Outdoors | May 13 | May 13 – May 27 |
| Direct Sow | May 6 | May 6 – May 27 |
| Harvest | July 15 | Jul 15 – Sep 23 |
| Fall Sowing | July 12 | Jul 12 – Jul 26 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Fall Sowing Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 2-3 times/week
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 5.5–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 5a
📆 Growing Season
123 days in Sheridan County
Growing Tips for Fennel (herb) in Sheridan County
Direct sow Fennel (herb) outdoors after May 20 in Sheridan 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.
Sheridan County receives only 15" of rain annually. Fennel (herb) needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
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 Sheridan County, WY?
Sheridan County is in Zone 5a with an average last frost of May 20. Plan your Fennel (herb) planting based on this frost date — see the calendar above for exact timing.
What planting zone is Sheridan County, WY?
Sheridan County, Wyoming is in USDA Hardiness Zone 5a. The average last spring frost is May 20 and first fall frost is September 20.
Your Sheridan County Garden Planner — Free
A 24-page printable planner built for Sheridan County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.