When to Plant Onion in Lea 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.
Lea County, New Mexico is in USDA Zone 7b. The average last spring frost is April 2 and the first fall frost is November 7, giving you a growing season of approximately 219 days.
At an elevation of 4,857 feet, Lea County receives approximately 17.1 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 93°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.
Lea County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.3-8.9
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 — Lea County, NM
Onion Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 26 | Feb 26 – Mar 12 |
| Transplant Outdoors | April 2 | Apr 2 – Apr 16 |
| Direct Sow | March 19 | Mar 19 – Apr 9 |
| Fall Sowing | August 29 | Aug 29 – Sep 12 |
| Harvest | July 2 | Jul 2 – Aug 20 |
Plant 1" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | — |
| July | Harvest |
| August | Fall Sowing Harvest |
| September | Fall Sowing |
| October | — |
| 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 7b
Growing Season
219 days
Growing Tips for Lea 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 Lea County, NM?
Lea County is in Zone 7b with an average last frost of April 2. Plan your Onion planting based on this frost date — see the calendar above for exact timing.
What planting zone is Lea County, NM?
Lea County, New Mexico is in USDA Hardiness Zone 7b. The average last spring frost is April 2 and first fall frost is November 7.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Lea County gardeners in Zone 7b organize planting dates, track what's growing, and never miss a planting window.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.