When to Plant Soybeans in Stephens County, OK
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.
Stephens County, Oklahoma is in USDA Zone 7b. The average last spring frost is April 6 and the first fall frost is November 1, giving you a growing season of approximately 209 days.
At an elevation of 979 feet, Stephens County receives approximately 26.1 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Soybeans during the growing season.
Stephens County Soil Profile
Soil Type
Loam
Soil pH
6.3-7.6
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 Stephens County
How your county's soil matches Soybeans's growing requirements.
Soil pH
Your soil pH (6.3–7.6) overlaps with Soybeans's range (6.0–7.0), though not a perfect match.
Soil Texture
The loam soil in Stephens County is excellent for Soybeans — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.3%) — Soybeans will thrive.
How to Plant Soybeans
Succession Planting Soybeans
Sow every 9.1 weeks. Last sowing by Jul 04 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — 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 | — | 0.6" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 1.6" | 0" | ❄️ Dormant |
| Apr | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| May | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Jun | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 3" | 1.3" | 💧 Light watering |
| Aug | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Sep | 4.3" | 2.4" | 1.9" | 💧 Light watering |
| Oct | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Nov | 4.3" | 0.8" | 3.5" | 🚿 Regular watering |
| Dec | — | 0.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Nov in Stephens 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 — Stephens County, OK
Soybeans Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | April 13 | Apr 13 – May 4 |
| Harvest | July 6 | Jul 6 – Aug 31 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Direct Sow |
| May | Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| 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: acceptable
🗺️ USDA Zone
Zone 7b
📆 Growing Season
209 days in Stephens County
Growing Tips for Soybeans in Stephens County
Direct sow Soybeans outdoors after April 06 in Stephens 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.
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
Check more plant combinations with our Companion Planting Checker →
Soybeans in Other Locations
Frequently Asked Questions
When should I plant Soybeans in Stephens County, OK?
Stephens County is in Zone 7b with an average last frost of April 6. Plan your Soybeans planting based on this frost date — see the calendar above for exact timing.
What planting zone is Stephens County, OK?
Stephens County, Oklahoma is in USDA Hardiness Zone 7b. The average last spring frost is April 6 and first fall frost is November 1.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Stephens County gardeners in Zone 7b organize planting dates, track what's growing, and never miss a planting window.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.