When to Plant Soybeans in Union Parish, LA
May to-do list for Union Parish, Louisiana
Your garden in Union Parish, Louisiana is working on a schedule, even when you're not. Here's where you should be this May.
June prep starts now
- First harvests: soybeans
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.
Union Parish, Louisiana is in USDA Zone 8b. The average last spring frost is March 22 and the first fall frost is November 5, giving you a growing season of approximately 228 days.
At an elevation of 426 feet, Union Parish receives approximately 57.4 inches of rainfall annually with predominantly loam soil. Summer highs average 96°F, so Soybeans may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Soybeans root diseases.
Union Parish Soil Profile
Soil Type
Loam
Soil pH
5.9-7
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 Union Parish
How your county's soil matches Soybeans's growing requirements.
Soil pH
Your soil pH (5.9–7.0) overlaps with Soybeans's range (6.0–7.0), though not a perfect match.
Soil Texture
The loam soil in Union Parish is excellent for Soybeans — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.9%). Annual compost additions will help Soybeans.
How to Plant Soybeans
Succession Planting Soybeans
Sow every 9.1 weeks. Last sowing by Jul 08 to harvest before frost.
Plant Water Budget
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 | — | 4.6" | 0" | ❄️ Dormant |
| Feb | — | 4.7" | 0" | ❄️ Dormant |
| Mar | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| May | 4.3" | 5.2" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 5.3" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 6.1" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 5.4" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 5" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Nov | 4.3" | 4.5" | 0" | ✅ Rainfall sufficient |
| Dec | — | 3.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Union Parish). 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 — Union Parish, LA
Soybeans Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | March 29 | Mar 29 – Apr 19 |
| Harvest | June 21 | Jun 21 – Aug 16 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Direct Sow |
| April | Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
80–120 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 8b
📆 Growing Season
228 days in Union Parish
Growing Tips for Soybeans in Union Parish
Direct sow Soybeans outdoors after March 22 in Union Parish when soil has warmed and frost danger has passed.
With summer highs reaching 96°F in Union Parish, provide afternoon shade for Soybeans and water deeply in the morning.
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 Union Parish, LA?
Union Parish is in Zone 8b with an average last frost of March 22. Plan your Soybeans planting based on this frost date — see the calendar above for exact timing.
What planting zone is Union Parish, LA?
Union Parish, Louisiana is in USDA Hardiness Zone 8b. The average last spring frost is March 22 and first fall frost is November 5.
Your Union Parish Garden Planner — Free
A 24-page printable planner built for Union Parish (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.