When to Plant Fava Beans in Fayette County, IA
Fava beans are a cool-season legume with large, meaty beans inside thick pods. They fix nitrogen in the soil and are one of the oldest cultivated crops.
Fayette County, Iowa is in USDA Zone 4b. The average last spring frost is May 5 and the first fall frost is October 5, giving you a growing season of approximately 153 days.
At an elevation of 1,228 feet, Fayette County receives approximately 41.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Fava Beans to ensure they mature before fall.
Fayette County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-6.8
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 Fayette County
How your county's soil matches Fava Beans's growing requirements.
Soil pH
Your soil pH (6.2–6.8) is within Fava Beans's preferred range (6.0–7.0).
Soil Texture
The silt loam soil in Fayette County is excellent for Fava Beans — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.5%) — Fava Beans will thrive.
How to Plant Fava Beans
Fall planting: Sow 12 weeks before your first frost date for a fall harvest.
Succession Planting Fava Beans
Sow every 8.6 weeks. Last sowing by Jun 27 to harvest before frost.
For a dedicated fall crop, sow by Jul 13.
Plant Water Budget
Monthly Watering Guide for Fava Beans
Fava Beans needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Fava Beans Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.9" | 0" | ❄️ Dormant |
| Feb | — | 2.1" | 0" | ❄️ Dormant |
| Mar | — | 2.5" | 0" | ❄️ Dormant |
| Apr | — | 4.5" | 0" | ❄️ Dormant |
| May | 4.3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4.8" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Oct | 4.3" | 3.3" | 1" | 💧 Light watering |
| Nov | — | 2.8" | 0" | ❄️ Dormant |
| Dec | — | 2.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Fayette County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Fava Beans 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.
Fava Beans Planting Timeline — Fayette County, IA
Fava Beans Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 24 | Mar 24 – Apr 7 |
| Transplant Outdoors | May 5 | May 5 – May 19 |
| Direct Sow | April 28 | Apr 28 – May 19 |
| Harvest | July 21 | Jul 21 – Sep 1 |
| Fall Sowing | July 13 | Jul 13 – Jul 27 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Direct Sow |
| 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 · Natural rainfall sufficient
📅 Days to Maturity
75–100 days
🧪 Soil pH
Needs 6–7 · Your soil: ideal
🗺️ USDA Zone
Zone 4b
📆 Growing Season
153 days in Fayette County
Growing Tips for Fava Beans in Fayette County
Direct sow Fava Beans outdoors after May 05 in Fayette County when soil has warmed and frost danger has passed.
Common pests for Fava Beans in this region include bean beetles and aphids. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct sow as early as soil can be worked in spring. Pinch growing tips when pods begin to form to redirect energy and reduce aphid problems. Stake tall varieties.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Fava Beans in Other Locations
Frequently Asked Questions
When should I plant Fava Beans in Fayette County, IA?
Fayette County is in Zone 4b with an average last frost of May 5. Plan your Fava Beans planting based on this frost date — see the calendar above for exact timing.
What planting zone is Fayette County, IA?
Fayette County, Iowa is in USDA Hardiness Zone 4b. The average last spring frost is May 5 and first fall frost is October 5.
Plan Your Garden with Confidence
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