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When to Plant Black Beans in Jackson County, CO

Black beans are a warm-season legume producing small, dark, protein-rich beans that are a staple in Latin American and Caribbean cuisines.

Jackson County, Colorado is in USDA Zone 3b. The average last spring frost is June 13 and the first fall frost is September 4, giving you a growing season of approximately 83 days.

At an elevation of 5,388 feet, Jackson County receives approximately 20.9 inches of rainfall annually with predominantly loam soil. Summer highs average 80ยฐF, so choose short-season varieties of Black Beans to ensure they mature before fall.

Jackson County, CO (Zone 3b) Very short season
83 days
Last Spring Frost June 13
83 growing days
First Fall Frost September 4

Jackson County Soil Profile

Soil Type

Loam

Soil pH

6.6-8.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Jun 8 🍅 Harvest: Sep 7 – Oct 12
Recommended (50%) ✗ May not fit
Transplant: Jun 13 🍅 Harvest: Sep 12 – Oct 17
Safe Start (90%) ✗ May not fit
Transplant: Jun 25 🍅 Harvest: Sep 24 – Oct 29

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 Jackson County

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

Soil pH

Your soil pH (6.6โ€“8.1) overlaps with Black Beans's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The loam soil in Jackson County is excellent for Black Beans โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Black Beans.

How to Plant Black Beans

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Black Beans

Black 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 Black Beans Needs Rainfall You Supplement Action
Jan โ€” 1.6" 0" โ„๏ธ Dormant
Feb โ€” 1.1" 0" โ„๏ธ Dormant
Mar โ€” 1.9" 0" โ„๏ธ Dormant
Apr โ€” 2.3" 0" โ„๏ธ Dormant
May โ€” 2.2" 0" โ„๏ธ Dormant
Jun 4.3" 1.7" 2.6" ๐Ÿšฟ Regular watering
Jul 4.3" 1.7" 2.6" ๐Ÿšฟ Regular watering
Aug 4.3" 2.5" 1.8" ๐Ÿ’ง Light watering
Sep 4.3" 1.5" 2.8" ๐Ÿšฟ Regular watering
Oct โ€” 2.1" 0" โ„๏ธ Dormant
Nov โ€” 1.4" 0" โ„๏ธ Dormant
Dec โ€” 1.1" 0" โ„๏ธ Dormant

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

Black 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.

Black Beans needs ~1,050 GDD — county provides 830 GDD May not mature

Black Beans Planting Timeline โ€” Jackson County, CO

Black Beans Planting Calendar

Activity When Date Range
Direct Sow June 27 Jun 27 โ€“ Jul 18
Harvest September 26 Sep 26 โ€“ Oct 31

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May โ€”
June Direct Sow
July Direct Sow
August โ€”
September Harvest
October Harvest
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

90โ€“120 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 3b

๐Ÿ“† Growing Season

83 days in Jackson County

Growing Tips for Black Beans in Jackson County

Direct sow Black Beans outdoors after June 13 in Jackson County when soil has warmed and frost danger has passed.

Your 83.0-day growing season in Jackson County is tight for Black Beans (90.0-120.0 days to maturity). Start indoors and choose early-maturing varieties.

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

Jackson County receives only 21" of rain annually. Black Beans needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Direct sow after last frost. Provide support for climbing varieties. Allow pods to dry fully on the vine before harvesting. Thresh dried pods by hand or in a pillowcase.

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 Black Beans in Jackson County, CO?

Jackson County is in Zone 3b with an average last frost of June 13. Plan your Black Beans planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Jackson County, CO?

Jackson County, Colorado is in USDA Hardiness Zone 3b. The average last spring frost is June 13 and first fall frost is September 4.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Jackson County gardeners in Zone 3b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

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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 Jackson County, CO. Local conditions may vary. Last updated: April 2026.