When to Plant Onion in Apache County, AZ
Onions are a fundamental kitchen staple available in yellow, white, and red varieties. Choose long-day, short-day, or intermediate types based on your latitude.
Apache County, Arizona is in USDA Zone 5b. The average last spring frost is May 20 and the first fall frost is October 10, giving you a growing season of approximately 143 days.
At an elevation of 7,720 feet, Apache County receives approximately 9.4 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 92°F, providing good warmth for Onion during the growing season. Sandy soil warms quickly in spring — great for early planting — but Onion will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Onion successfully. Mulch heavily to conserve soil moisture.
Apache County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.2-8.7
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 Apache County
How your county's soil matches Onion's growing requirements.
Soil pH
Your soil pH (7.2–8.7) is more alkaline than Onion prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
Sandy soil in Apache County warms quickly in spring but drains fast. Onion will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Onion.
Organic Matter
Organic matter is low (0.8%). Add 2-3 inches of compost before planting Onion.
How to Plant Onion
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Plant Water Budget
Water stress score is 10/10 — consider drought-tolerant varieties and mulching
Onion Planting Timeline — Apache County, AZ
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 15 | Apr 15 – Apr 29 |
| Transplant Outdoors | May 20 | May 20 – Jun 3 |
| Direct Sow | May 6 | May 6 – May 27 |
| Fall Sowing | August 1 | Aug 1 – Aug 15 |
| Harvest | August 19 | Aug 19 – Oct 7 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors |
| July | — |
| August | Fall Sowing Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · 2-3 times/week
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6–7 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 5b
📆 Growing Season
143 days in Apache County
Growing Tips for Onion in Apache County
Direct sow Onion outdoors after May 20 in Apache County when soil has warmed and frost danger has passed.
Sandy soil in Apache County dries quickly — mulch Onion with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Common pests for Onion in this region include onion maggots and thrips. Use row covers early in the season and inspect plants weekly.
Apache County receives only 9" of rain annually. Onion needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Start seeds indoors 8-10 weeks before transplanting. Match day-length type to your latitude. Stop watering when tops begin to fall over and cure bulbs for 2-3 weeks before storage.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Onion in Other Locations
Frequently Asked Questions
When should I plant Onion in Apache County, AZ?
Apache County is in Zone 5b with an average last frost of May 20. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Apache County, AZ?
Apache County, Arizona is in USDA Hardiness Zone 5b. The average last spring frost is May 20 and first fall frost is October 10.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Apache County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.
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