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When to Plant Black Beans in Barnes County, ND

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

Barnes County, North Dakota is in USDA Zone 4a. The average last spring frost is May 9 and the first fall frost is September 29, giving you a growing season of approximately 143 days.

At an elevation of 623 feet, Barnes County receives approximately 20.5 inches of rainfall annually with predominantly loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Black Beans to ensure they mature before fall.

Barnes County, ND (Zone 4a) Short season
143 days
Last Spring Frost May 9
143 growing days
First Fall Frost September 29

Barnes County Soil Profile

Soil Type

Loam

Soil pH

6.3-7.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (6 days to spare)
Transplant: May 1 🍅 Harvest: Jul 31 – Sep 18
Recommended (50%) ✓ Fits season (3 days to spare)
Transplant: May 9 🍅 Harvest: Aug 8 – Sep 26
Safe Start (90%) ✓ Fits season (9 days to spare)
Transplant: May 19 🍅 Harvest: Aug 18 – Oct 6

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 Barnes County

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

Soil pH

Your soil pH (6.3โ€“7.7) overlaps with Black Beans's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.7%). 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
0.6″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 506 gal / 100 sq ft

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€” 0.5" 0" โ„๏ธ Dormant
Feb โ€” 0.6" 0" โ„๏ธ Dormant
Mar โ€” 1.4" 0" โ„๏ธ Dormant
Apr โ€” 2.1" 0" โ„๏ธ Dormant
May 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Jun 4.3" 2.8" 1.5" ๐Ÿ’ง Light watering
Jul 4.3" 3" 1.3" ๐Ÿ’ง Light watering
Aug 4.3" 2.6" 1.7" ๐Ÿ’ง Light watering
Sep 4.3" 1.9" 2.4" ๐Ÿšฟ Regular watering
Oct โ€” 1.1" 0" โ„๏ธ Dormant
Nov โ€” 0.8" 0" โ„๏ธ Dormant
Dec โ€” 0.5" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Sep in Barnes 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 ~1,365 GDD — county provides 1,859 GDD Excellent fit

Black Beans Planting Timeline โ€” Barnes County, ND

Black Beans Planting Calendar

Activity When Date Range
Direct Sow May 23 May 23 โ€“ Jun 13
Harvest August 22 Aug 22 โ€“ Oct 10

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

90โ€“120 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 4a

๐Ÿ“† Growing Season

143 days in Barnes County

Growing Tips for Black Beans in Barnes County

Direct sow Black Beans outdoors after May 09 in Barnes County when soil has warmed and frost danger has passed.

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

Barnes County receives only 20" 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 Barnes County, ND?

Barnes County is in Zone 4a with an average last frost of May 9. Plan your Black Beans planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Barnes County, ND?

Barnes County, North Dakota is in USDA Hardiness Zone 4a. The average last spring frost is May 9 and first fall frost is September 29.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Barnes County gardeners in Zone 4a 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.

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