When to Plant Onion in McKinley County, NM
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.
McKinley County, New Mexico is in USDA Zone 5b. The average last spring frost is May 29 and the first fall frost is September 24, giving you a growing season of approximately 118 days.
At an elevation of 7,104 feet, McKinley County receives approximately 10.5 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 86°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.
McKinley County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.3-8.2
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.
Plant Water Budget
Water stress score is 10/10 — consider drought-tolerant varieties and mulching
Onion Planting Timeline — McKinley County, NM
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 24 | Apr 24 – May 8 |
| Transplant Outdoors | May 29 | May 29 – Jun 12 |
| Direct Sow | May 15 | May 15 – Jun 5 |
| Fall Sowing | July 16 | Jul 16 – Jul 30 |
| Harvest | August 28 | Aug 28 – Oct 16 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors |
| May | Start Indoors Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Fall Sowing |
| August | Harvest |
| September | Harvest |
| October | Harvest |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
90–120 days
Soil pH
6 – 7
USDA Zone
Zone 5b
Growing Season
118 days
Growing Tips for McKinley County
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 McKinley County, NM?
McKinley County is in Zone 5b with an average last frost of May 29. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is McKinley County, NM?
McKinley County, New Mexico is in USDA Hardiness Zone 5b. The average last spring frost is May 29 and first fall frost is September 24.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help McKinley County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.
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