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When to Plant Fava Beans in Colfax County, NM

Fava beans are a cool-season legume with large, meaty beans inside thick pods. They fix nitrogen in the soil and are one of the oldest cultivated crops.

Colfax County, New Mexico is in USDA Zone 5a. The average last spring frost is May 15 and the first fall frost is September 26, giving you a growing season of approximately 134 days.

At an elevation of 5,131 feet, Colfax County receives approximately 15.5 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Fava Beans to ensure they mature before fall. Sandy soil warms quickly in spring โ€” great for early planting โ€” but Fava Beans will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Fava Beans successfully. Mulch heavily to conserve soil moisture.

Colfax County, NM (Zone 5a) Short season
134 days
Last Spring Frost May 15
134 growing days
First Fall Frost September 26

Colfax County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.1-8.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (15 days to spare)
Start indoors: Apr 1 Transplant: May 6 🍅 Harvest: Jul 22 – Sep 2
Recommended (50%) ✓ Fits season (15 days to spare)
Start indoors: Apr 10 Transplant: May 15 🍅 Harvest: Jul 31 – Sep 11
Safe Start (90%) ✗ May not fit
Start indoors: May 12 Transplant: Jun 16 🍅 Harvest: Sep 1 – Oct 13

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 Colfax County

How your county's soil matches Fava Beans's growing requirements.

Soil pH

Your soil pH (7.1โ€“8.1) is more alkaline than Fava Beans prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Colfax County warms quickly in spring but drains fast. Fava Beans will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Fava Beans.

Organic Matter

Organic matter is low (0.9%). Add 2-3 inches of compost before planting Fava Beans.

How to Plant Fava Beans

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.5″/week
You supply
1.0″/week
Watering frequency 2-3 times/week
Season total 1,165 gal / 100 sq ft
Drought risk

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

Monthly Watering Guide for Fava Beans

Fava Beans needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Fava Beans Needs Rainfall You Supplement Action
Jan โ€” 1.1" 0" โ„๏ธ Dormant
Feb โ€” 0.8" 0" โ„๏ธ Dormant
Mar โ€” 0.9" 0" โ„๏ธ Dormant
Apr โ€” 0.5" 0" โ„๏ธ Dormant
May 4.3" 0.4" 3.9" ๐Ÿšฟ Regular watering
Jun 4.3" 0.5" 3.8" ๐Ÿšฟ Regular watering
Jul 4.3" 3" 1.3" ๐Ÿ’ง Light watering
Aug 4.3" 2.9" 1.4" ๐Ÿ’ง Light watering
Sep 4.3" 2" 2.3" ๐Ÿšฟ Regular watering
Oct โ€” 1.3" 0" โ„๏ธ Dormant
Nov โ€” 1" 0" โ„๏ธ Dormant
Dec โ€” 1" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Sep in Colfax County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Fava Beans 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" โ€” every day above 50ยฐF 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.

Fava Beans needs ~1,138 GDD — county provides 1,742 GDD Excellent fit

Fava Beans Planting Timeline โ€” Colfax County, NM

Fava Beans Planting Calendar

Activity When Date Range
Start Indoors April 10 Apr 10 โ€“ Apr 24
Transplant Outdoors May 15 May 15 โ€“ May 29
Direct Sow May 1 May 1 โ€“ May 22
Harvest July 31 Jul 31 โ€“ Sep 11
Fall Sowing July 18 Jul 18 โ€“ Aug 1

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 2-3 times/week

๐Ÿ“… Days to Maturity

75โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 5a

๐Ÿ“† Growing Season

134 days in Colfax County

Growing Tips for Fava Beans in Colfax County

Direct sow Fava Beans outdoors after May 15 in Colfax County when soil has warmed and frost danger has passed.

Sandy soil in Colfax County dries quickly โ€” mulch Fava Beans with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

Common pests for Fava Beans in this region include bean beetles and aphids. Use row covers early in the season and inspect plants weekly.

Colfax County receives only 16" of rain annually. Fava Beans needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct sow as early as soil can be worked in spring. Pinch growing tips when pods begin to form to redirect energy and reduce aphid problems. Stake tall varieties.

Companion Planting

Good Companions

Avoid Planting Near

  • Onion
  • Garlic

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Fava Beans in Colfax County, NM?

Colfax County is in Zone 5a with an average last frost of May 15. Plan your Fava Beans planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Colfax County, NM?

Colfax County, New Mexico is in USDA Hardiness Zone 5a. The average last spring frost is May 15 and first fall frost is September 26.

๐ŸŒฑ

Plan Your Garden with Confidence

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

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