When to Plant Fava Beans in Grant County, OR
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.
Grant County, Oregon is in USDA Zone 5b. The average last spring frost is June 6 and the first fall frost is September 10, giving you a growing season of approximately 96 days.
At an elevation of 2,838 feet, Grant County receives approximately 22.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Fava Beans to ensure they mature before fall.
Grant County Soil Profile
Soil Type
Silt Loam
Soil pH
5.4-6.4
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 Grant County
How your county's soil matches Fava Beans's growing requirements.
Soil pH
Your soil pH (5.4–6.4) is more acidic than Fava Beans prefers (6.0–7.0). Add garden lime to raise pH.
Soil Texture
The silt loam soil in Grant County is excellent for Fava Beans — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Fava Beans.
Organic Matter
Organic matter is excellent (4.8%) — Fava Beans will thrive.
How to Plant Fava Beans
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
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 | — | 3.2" | 0" | ❄️ Dormant |
| Feb | — | 2.9" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | — | 1.5" | 0" | ❄️ Dormant |
| May | — | 1.3" | 0" | ❄️ Dormant |
| Jun | 4.3" | 0.8" | 3.5" | 🚿 Regular watering |
| Jul | 4.3" | 0.4" | 3.9" | 🚿 Regular watering |
| Aug | 4.3" | 0.4" | 3.9" | 🚿 Regular watering |
| Sep | 4.3" | 0.9" | 3.4" | 🚿 Regular watering |
| Oct | — | 1.8" | 0" | ❄️ Dormant |
| Nov | — | 3.1" | 0" | ❄️ Dormant |
| Dec | — | 3.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Grant 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 — Grant County, OR
Fava Beans Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | May 2 | May 2 – May 16 |
| Transplant Outdoors | June 6 | Jun 6 – Jun 20 |
| Direct Sow | May 23 | May 23 – Jun 13 |
| Harvest | August 22 | Aug 22 – Oct 3 |
| Fall Sowing | July 2 | Jul 2 – Jul 16 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Start Indoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Fall Sowing |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
75–100 days
🧪 Soil pH
Needs 6–7 · Your soil: too_acidic
🗺️ USDA Zone
Zone 5b
📆 Growing Season
96 days in Grant County
Growing Tips for Fava Beans in Grant County
Direct sow Fava Beans outdoors after June 06 in Grant County when soil has warmed and frost danger has passed.
Your 96.0-day growing season in Grant County is tight for Fava Beans (75.0-100.0 days to maturity). Start indoors and choose early-maturing varieties.
Common pests for Fava Beans in this region include bean beetles and aphids. Use row covers early in the season and inspect plants weekly.
Grant County receives only 23" of rain annually. Fava Beans needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
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 Grant County, OR?
Grant County is in Zone 5b with an average last frost of June 6. Plan your Fava Beans planting based on this frost date — see the calendar above for exact timing.
What planting zone is Grant County, OR?
Grant County, Oregon is in USDA Hardiness Zone 5b. The average last spring frost is June 6 and first fall frost is September 10.
Plan Your Garden with Confidence
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