When to Plant Soybeans in Nez Perce County, ID
Soybeans (edamame) are a high-protein legume that fixes nitrogen in the soil. Fresh green soybeans harvested at the edamame stage are a nutritious snack.
Nez Perce County, Idaho is in USDA Zone 6b. The average last spring frost is May 12 and the first fall frost is September 26, giving you a growing season of approximately 137 days.
At an elevation of 4,819 feet, Nez Perce County receives approximately 16.7 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Soybeans during the growing season. With low rainfall, drip irrigation is essential for growing Soybeans successfully. Mulch heavily to conserve soil moisture.
Nez Perce County Soil Profile
Soil Type
Loam
Soil pH
6.6-8
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 Nez Perce County
How your county's soil matches Soybeans's growing requirements.
Soil pH
Your soil pH (6.6–8.0) is more alkaline than Soybeans prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Nez Perce County is excellent for Soybeans — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Soybeans.
How to Plant Soybeans
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Soybeans
Soybeans needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Soybeans Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.2" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 1.5" | 0" | ❄️ Dormant |
| Apr | — | 1.7" | 0" | ❄️ Dormant |
| May | 4.3" | 1.8" | 2.5" | 🚿 Regular watering |
| Jun | 4.3" | 1.2" | 3.1" | 🚿 Regular watering |
| Jul | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Aug | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Sep | 4.3" | 1.2" | 3.1" | 🚿 Regular watering |
| Oct | — | 1.7" | 0" | ❄️ Dormant |
| Nov | — | 1.1" | 0" | ❄️ Dormant |
| Dec | — | 1.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Nez Perce County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Soybeans 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.
Soybeans Planting Timeline — Nez Perce County, ID
Soybeans Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | May 19 | May 19 – Jun 9 |
| Harvest | August 11 | Aug 11 – Oct 6 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Direct Sow |
| June | Direct Sow |
| July | — |
| 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
80–120 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 6b
📆 Growing Season
137 days in Nez Perce County
Growing Tips for Soybeans in Nez Perce County
Direct sow Soybeans outdoors after May 12 in Nez Perce County when soil has warmed and frost danger has passed.
Common pests for Soybeans in this region include bean beetles and aphids. Use row covers early in the season and inspect plants weekly.
Nez Perce County receives only 17" of rain annually. Soybeans needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Direct sow after soil warms to 60F. Plant in blocks rather than rows for better pollination. Harvest for edamame when pods are plump and bright green.
Companion Planting
Good Companions
Avoid Planting Near
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Soybeans in Other Locations
Frequently Asked Questions
When should I plant Soybeans in Nez Perce County, ID?
Nez Perce County is in Zone 6b with an average last frost of May 12. Plan your Soybeans planting based on this frost date — see the calendar above for exact timing.
What planting zone is Nez Perce County, ID?
Nez Perce County, Idaho is in USDA Hardiness Zone 6b. The average last spring frost is May 12 and first fall frost is September 26.
Plan Your Garden with Confidence
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