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When to Plant Lettuce in Rio Arriba County, NM

Lettuce is a fast-growing cool-season green available in leaf, romaine, butterhead, and crisphead types. It is the foundation of salads and one of the easiest crops to grow.

Rio Arriba County, New Mexico is in USDA Zone 5b. The average last spring frost is June 13 and the first fall frost is September 17, giving you a growing season of approximately 96 days.

At an elevation of 5,979 feet, Rio Arriba County receives approximately 17.4 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Lettuce to ensure they mature before fall. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Lettuce will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Lettuce successfully. Mulch heavily to conserve soil moisture.

Rio Arriba County, NM (Zone 5b) Very short season
96 days
Last Spring Frost June 13
96 growing days
First Fall Frost September 17

Rio Arriba County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.3-8.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: May 2 Transplant: Jun 6 🍅 Harvest: Jul 11 – Sep 19
Recommended (50%) ✗ May not fit
Start indoors: May 9 Transplant: Jun 13 🍅 Harvest: Jul 18 – Sep 26
Safe Start (90%) ✗ May not fit
Start indoors: May 20 Transplant: Jun 24 🍅 Harvest: Jul 29 – Oct 7

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

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.7″/week
Watering frequency 1-2 times/week
Season total 552 gal / 100 sq ft
Drought risk

Water stress score is 10/10 โ€” consider drought-tolerant varieties and mulching

Lettuce needs ~585 GDD — county provides 1,248 GDD Excellent fit

Lettuce Planting Timeline โ€” Rio Arriba County, NM

Lettuce Planting Calendar

Activity When Date Range
Start Indoors May 9 May 9 โ€“ May 23
Transplant Outdoors June 13 Jun 13 โ€“ Jun 27
Direct Sow May 30 May 30 โ€“ Jun 20
Fall Sowing July 9 Jul 9 โ€“ Jul 23
Harvest July 18 Jul 18 โ€“ Sep 26

Plant 0.5" deep ยท 6" apart ยท Rows 12" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Start Indoors Direct Sow
June Transplant Outdoors Direct Sow
July Fall Sowing Harvest
August Harvest
September Harvest
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Partial Shade (3-6 hours)

Water

Moderate โ€” regular watering

Days to Maturity

30โ€“60 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 5b

Growing Season

96 days

Growing Tips for Rio Arriba County

Sow seeds directly every 2 weeks for continuous harvest. Provide afternoon shade in warm weather to delay bolting. Harvest in the morning for crispest leaves.

Companion Planting

Good Companions

Avoid Planting Near

  • Celery

Level Up Your Garden

๐ŸŒพ Save Your Own Lettuce Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Let plants bolt and flower. Harvest seed heads when fluffy.
Storage Store airtight; viable 6 years at 35ยฐF, under 45% humidity.

Very easy to save. Let a few plants bolt each season.

Frequently Asked Questions

When should I plant Lettuce in Rio Arriba County, NM?

Rio Arriba County is in Zone 5b with an average last frost of June 13. Plan your Lettuce planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Rio Arriba County, NM?

Rio Arriba County, New Mexico is in USDA Hardiness Zone 5b. The average last spring frost is June 13 and first fall frost is September 17.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Rio Arriba County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

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Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Rio Arriba County, NM. Local conditions may vary. Last updated: April 2026.