When to Plant Edamame in Washington County, TX
What to do in May
Your Washington County, Texas garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.
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Start harvesting edamame
Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.
June prep starts now
- First harvests: edamame
Edamame are soybeans harvested at the immature green stage for a sweet, nutty snack. They are high in protein and easy to grow in warm climates.
Washington County, Texas is in USDA Zone 9a. The average last spring frost is March 2 and the first fall frost is November 27, giving you a growing season of approximately 270 days.
At an elevation of 386 feet, Washington County receives approximately 58.9 inches of rainfall annually with predominantly clay soil. Summer highs average 90°F, providing good warmth for Edamame during the growing season. Clay soil retains moisture well for Edamame, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Edamame root diseases.
Washington County Soil Profile
Soil Type
Clay
Soil pH
6.9-8.4
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 Washington County
How your county's soil matches Edamame's growing requirements.
Soil pH
Your soil pH (6.9–8.4) is more alkaline than Edamame prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
Your clay soil in Washington County is workable for Edamame. Add compost annually to improve structure.
Organic Matter
Organic matter is moderate (2.6%). Annual compost additions will help Edamame.
How to Plant Edamame
Succession Planting Edamame
Sow every 8.6 weeks. Last sowing by Aug 19 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Edamame
Edamame needs approximately 0.9 inches of water per week (3.9" per month). Here's how your county's rainfall compares month by month.
| Month | Edamame Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.9" | 0" | ❄️ Dormant |
| Mar | 3.9" | 4.3" | 0" | ✅ Rainfall sufficient |
| Apr | 3.9" | 5.8" | 0" | ✅ Rainfall sufficient |
| May | 3.9" | 8.3" | 0" | ✅ Rainfall sufficient |
| Jun | 3.9" | 9.9" | 0" | ✅ Rainfall sufficient |
| Jul | 3.9" | 7" | 0" | ✅ Rainfall sufficient |
| Aug | 3.9" | 7.4" | 0" | ✅ Rainfall sufficient |
| Sep | 3.9" | 5.2" | 0" | ✅ Rainfall sufficient |
| Oct | 3.9" | 4.2" | 0" | ✅ Rainfall sufficient |
| Nov | 3.9" | 2" | 1.9" | 💧 Light watering |
| Dec | — | 1.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Washington County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Edamame 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.
Edamame Planting Timeline — Washington County, TX
Edamame Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | March 9 | Mar 9 – Mar 30 |
| Harvest | May 25 | May 25 – Jul 6 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Direct Sow |
| April | — |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.9"/week · Natural rainfall sufficient
📅 Days to Maturity
75–100 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 9a
📆 Growing Season
270 days in Washington County
Growing Tips for Edamame in Washington County
Direct sow Edamame outdoors after March 02 in Washington County when soil has warmed and frost danger has passed.
With Washington County's clay soil (37% clay), work in 3-4 inches of compost before planting Edamame. Avoid tilling when soil is wet to prevent compaction.
Common pests for Edamame 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 is warm. Do not over-fertilize with nitrogen. Harvest when pods are plump and bright green but before they start to yellow. Steam or boil pods before eating.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Edamame in Other Locations
Frequently Asked Questions
When should I plant Edamame in Washington County, TX?
Washington County is in Zone 9a with an average last frost of March 2. Plan your Edamame planting based on this frost date — see the calendar above for exact timing.
What planting zone is Washington County, TX?
Washington County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is March 2 and first fall frost is November 27.
Your Washington County Garden Planner — Free
A 24-page printable planner built for Washington County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.