When to Plant Soybeans in Yuma County, AZ
Top priorities for Yuma County, Arizona gardeners in May
May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Yuma County, Arizona.
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It's harvest week for soybeans
Check every 1–2 days. Many of these get tough or go to seed if you wait too long.
Coming up in June — start thinking about
- 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.
Yuma County, Arizona is in USDA Zone 10a. The average last spring frost is February 10 and the first fall frost is December 1, giving you a growing season of approximately 294 days.
At an elevation of 4,781 feet, Yuma County receives approximately 9.4 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 92°F, providing good warmth for Soybeans during the growing season. Sandy soil warms quickly in spring — great for early planting — but Soybeans will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Soybeans successfully. Mulch heavily to conserve soil moisture.
Yuma County Soil Profile
Soil Type
Sandy Loam
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 Yuma County
How your county's soil matches Soybeans's growing requirements.
Soil pH
Your soil pH (6.9–8.4) is more alkaline than Soybeans prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
Sandy soil in Yuma County warms quickly in spring but drains fast. Soybeans will need more frequent watering and regular compost additions to retain nutrients.
Organic Matter
Organic matter is low (0.8%). Add 2-3 inches of compost before planting Soybeans.
How to Plant Soybeans
Succession Planting Soybeans
Sow every 9.1 weeks. Last sowing by Aug 03 to harvest before frost.
Plant Water Budget
Water stress score is 10/10 — 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 | 4.3" | 0.5" | 3.8" | 🚿 Regular watering |
| Mar | 4.3" | 0.5" | 3.8" | 🚿 Regular watering |
| Apr | 4.3" | 0.3" | 4" | 🚿 Regular watering |
| May | 4.3" | 0.2" | 4.1" | 🚿 Regular watering |
| Jun | 4.3" | 0.3" | 4" | 🚿 Regular watering |
| Jul | 4.3" | 1.8" | 2.5" | 🚿 Regular watering |
| Aug | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Sep | 4.3" | 1.4" | 2.9" | 🚿 Regular watering |
| Oct | 4.3" | 0.8" | 3.5" | 🚿 Regular watering |
| Nov | 4.3" | 0.5" | 3.8" | 🚿 Regular watering |
| Dec | 4.3" | 0.6" | 3.7" | 🚿 Regular watering |
Water needs are for active growing months only (Feb–Dec in Yuma 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 — Yuma County, AZ
Soybeans Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | February 17 | Feb 17 – Mar 10 |
| Harvest | May 12 | May 12 – Jul 7 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Direct Sow |
| March | Direct Sow |
| April | — |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 2-3 times/week
📅 Days to Maturity
80–120 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 10a
📆 Growing Season
294 days in Yuma County
Growing Tips for Soybeans in Yuma County
Direct sow Soybeans outdoors after February 10 in Yuma County when soil has warmed and frost danger has passed.
Sandy soil in Yuma County dries quickly — mulch Soybeans with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Common pests for Soybeans in this region include bean beetles and aphids. Use row covers early in the season and inspect plants weekly.
Yuma County receives only 9" 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
Check more plant combinations with our Companion Planting Checker →
Soybeans in Other Locations
Frequently Asked Questions
When should I plant Soybeans in Yuma County, AZ?
Yuma County is in Zone 10a with an average last frost of February 10. Plan your Soybeans planting based on this frost date — see the calendar above for exact timing.
What planting zone is Yuma County, AZ?
Yuma County, Arizona is in USDA Hardiness Zone 10a. The average last spring frost is February 10 and first fall frost is December 1.
Your Yuma County Garden Planner — Free
A 24-page printable planner built for Yuma County (Zone 10a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.