When to plant Spinach in Yuma County, AZ
The best window to plant Spinach in Yuma County, is January 20–February 10, when soil warms to 50°F. Last frost typically hits February 10; first frost December 1. A second sowing from October 6 to October 20 extends the harvest into fall.
When to Plant Spinach in Yuma County, AZ
July to-do list for Yuma County, Arizona
Each item below is timed to Yuma County, Arizona's frost dates and soil temperatures. Skip nothing, stress about nothing.
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Plan the fall garden
Make a planting map for August. Tomatoes, peppers, brassicas, lettuce, root crops all go in over the next 8 weeks. Soil amendments and irrigation prep happen now.
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Keep heat-survivor crops productive
Daily harvest of okra and southern peas keeps plants producing. Let pods over-mature and the plant stops setting new fruit.
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Watch for hurricane prep season
August-October is hurricane season. Stake young trees, secure rain barrels, and plan how to protect tender transplants from high winds.
Spinach is a nutrient-packed cool-season green that grows quickly in spring and fall. It is rich in iron, vitamins, and antioxidants and excellent raw or cooked.
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 Spinach during the growing season. Sandy soil warms quickly in spring — great for early planting — but Spinach will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Spinach successfully. Mulch heavily to conserve soil moisture.
Yuma County Soil Profile
Soil Type
Sandy Loam
Soil pH
6.9-8.4
Drainage
Well Drained
Spinach 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 Spinach's growing requirements.
Soil pH
Your soil pH (6.9–8.4) is more alkaline than Spinach prefers (6.5–7.5). Add sulfur or peat moss to lower pH.
Soil Texture
Sandy soil in Yuma County warms quickly in spring but drains fast. Spinach 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 Spinach.
How to Plant Spinach
Fall planting: Sow 8 weeks before your first frost date for a fall harvest.
Succession Planting Spinach
Sow every 4 weeks. Last sowing by Oct 12 to harvest before frost.
For a dedicated fall crop, sow by Oct 06.
Spinach Water Budget
Water stress score is 10/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Spinach
Spinach needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.
| Month | Spinach Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 0.6" | 0" | ❄️ Dormant |
| Feb | 3" | 0.5" | 2.5" | 🚿 Regular watering |
| Mar | 3" | 0.5" | 2.5" | 🚿 Regular watering |
| Apr | 3" | 0.3" | 2.7" | 🚿 Regular watering |
| May | 3" | 0.2" | 2.8" | 🚿 Regular watering |
| Jun | 3" | 0.3" | 2.7" | 🚿 Regular watering |
| Jul | 3" | 1.8" | 1.2" | 💧 Light watering |
| Aug | 3" | 1.9" | 1.1" | 💧 Light watering |
| Sep | 3" | 1.4" | 1.6" | 🚿 Regular watering |
| Oct | 3" | 0.8" | 2.2" | 🚿 Regular watering |
| Nov | 3" | 0.5" | 2.5" | 🚿 Regular watering |
| Dec | 3" | 0.6" | 2.4" | 🚿 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.
Spinach 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.
Spinach Planting Timeline — Yuma County, AZ
Spinach Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 13 | Jan 13 – Jan 27 |
| Transplant Outdoors | February 10 | Feb 10 – Feb 24 |
| Direct Sow | January 20 | Jan 20 – Feb 10 |
| Harvest | March 17 | Mar 17 – May 19 |
| Fall Sowing | October 6 | Oct 6 – Oct 20 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors Direct Sow |
| February | Transplant Outdoors Direct Sow |
| March | Harvest |
| April | Harvest |
| May | Harvest |
| June | — |
| July | — |
| August | — |
| September | — |
| October | Fall Sowing |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
0.7"/week · 1-2 times/week
📅 Days to Maturity
35–50 days
🧪 Soil pH
Needs 6.5–7.5 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 10a
📆 Growing Season
294 days in Yuma County
Growing Tips for Spinach in Yuma County
Direct sow Spinach outdoors after February 10 in Yuma County when soil has warmed and frost danger has passed.
Sandy soil in Yuma County dries quickly — mulch Spinach with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Summer highs in Yuma County reach 92°F — grow Spinach as a spring or fall crop. Use shade cloth if planting in summer.
Your generous 295.0-day season in Yuma County allows multiple plantings of Spinach. Sow every 17.0 days for continuous harvest.
General growing tips
Direct sow as soon as soil can be worked in spring. Plant in partial shade for summer crops to delay bolting. Succession plant every 2 weeks for continuous harvest.
Recommended Spinach Varieties for Yuma County
Slow-bolting spinach for warm springs — best as fall crop here
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Wind pollinated — isolate 1/2 mile for purity. Easy to let bolt in heat.
Spinach in Other Locations
Frequently Asked Questions
When should I plant Spinach in Yuma County, AZ?
Yuma County is in Zone 10a with an average last frost of February 10. Plan your Spinach 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.
When should I plant Spinach in Yuma County, AZ?
In Yuma County, AZ, plant Spinach after the last frost (around February 10) and before the first frost (around December 1). Best results when soil holds above 50°F.
What growing zone is Yuma County, AZ for Spinach?
Yuma County sits in USDA Zone 10a. Spinach grows reliably in zones 2a through 10b, so it's a good fit here.
Can Spinach grow in Yuma County's climate?
Yes — Spinach grows well in Yuma County's temperate climate. Yuma County averages a 295-day frost-free season, with last frost around February 10 and first frost around December 1.
Your Yuma County Garden Planner — Free
A 22-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.