When to plant Soybeans in Marion County, MO
Soybeans planted in Marion County between April 21 and May 12 matures in 80–120 days — well before the October 21 first frost.
When to Plant Soybeans in Marion County, MO
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.
Marion County, Missouri is in USDA Zone 6a. The average last spring frost is April 14 and the first fall frost is October 21, giving you a growing season of approximately 190 days.
At an elevation of 1,252 feet, Marion County receives approximately 36.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Soybeans to ensure they mature before fall.
Marion County Soil Profile
Soil Type
Silt Loam
Soil pH
5.3-6.7
Drainage
Well Drained
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 | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | 4.3" | 4" | 0.3" | 💧 Light watering |
| May | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Aug | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Sep | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Oct | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| Nov | — | 2.4" | 0" | ❄️ Dormant |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Marion County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Soybeans Planting Timeline — Marion County, MO
Soybeans Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | April 21 | Apr 21 – May 12 |
| Harvest | July 14 | Jul 14 – Sep 8 |
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 | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
80–120 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 6a
📆 Growing Season
190 days in Marion County
Growing Tips for Marion County
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 Marion County, MO?
Marion County is in Zone 6a with an average last frost of April 14. Plan your Soybeans planting based on this frost date — see the calendar above for exact timing.
What planting zone is Marion County, MO?
Marion County, Missouri is in USDA Hardiness Zone 6a. The average last spring frost is April 14 and first fall frost is October 21.
When should I plant Soybeans in Marion County, MO?
In Marion County, MO, plant Soybeans after the last frost (around April 14) and before the first frost (around October 21). Best results when soil holds above 50°F.
What growing zone is Marion County, MO for Soybeans?
Marion County sits in USDA Zone 6a. Soybeans grows reliably in zones 3a through 10b, so it's a good fit here.
Can Soybeans grow in Marion County's climate?
Yes — Soybeans grows well in Marion County's temperate climate. Marion County averages a 190-day frost-free season, with last frost around April 14 and first frost around October 21.
Your Marion County Garden Planner — Free
A 22-page printable planner built for Marion County (Zone 6a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.