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When to Plant Scarlet Runner Beans in Adams County, ND

Scarlet runner beans are ornamental and edible climbing beans with vivid red flowers that attract hummingbirds. Both the young pods and mature beans are edible.

Adams County, North Dakota is in USDA Zone 4a. The average last spring frost is May 14 and the first fall frost is September 27, giving you a growing season of approximately 136 days.

At an elevation of 1,100 feet, Adams County receives approximately 27.4 inches of rainfall annually with predominantly loam soil. Summer highs average 81ยฐF, so choose short-season varieties of Scarlet Runner Beans to ensure they mature before fall.

Adams County, ND (Zone 4a) Short season
136 days
Last Spring Frost May 14
136 growing days
First Fall Frost September 27

Adams County Soil Profile

Soil Type

Loam

Soil pH

6.6-7.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (13 days to spare)
Start indoors: Mar 9 Transplant: Jun 1 🍅 Harvest: Aug 3 – Sep 7
Recommended (50%) ✓ Fits season (17 days to spare)
Start indoors: Mar 12 Transplant: Jun 4 🍅 Harvest: Aug 6 – Sep 10
Safe Start (90%) ✓ Fits season (21 days to spare)
Start indoors: Mar 23 Transplant: Jun 15 🍅 Harvest: Aug 17 – Sep 21

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 Adams County

How your county's soil matches Scarlet Runner Beans's growing requirements.

Soil pH

Your soil pH (6.6โ€“7.3) overlaps with Scarlet Runner Beans's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.2%). Annual compost additions will help Scarlet Runner Beans.

How to Plant Scarlet Runner Beans

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

Succession Planting Scarlet Runner Beans

2
successive plantings in your 136-day season

Sow every 6.9 weeks. Last sowing by Jul 09 to harvest before frost.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 223 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Scarlet Runner Beans

Scarlet Runner 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 Scarlet Runner Beans Needs Rainfall You Supplement Action
Jan โ€” 2" 0" โ„๏ธ Dormant
Feb โ€” 1.6" 0" โ„๏ธ Dormant
Mar โ€” 2.7" 0" โ„๏ธ Dormant
Apr โ€” 2.6" 0" โ„๏ธ Dormant
May 4.3" 2.9" 1.4" ๐Ÿ’ง Light watering
Jun 4.3" 1.8" 2.5" ๐Ÿšฟ Regular watering
Jul 4.3" 2.5" 1.8" ๐Ÿ’ง Light watering
Aug 4.3" 3.1" 1.2" ๐Ÿ’ง Light watering
Sep 4.3" 2.5" 1.8" ๐Ÿ’ง Light watering
Oct โ€” 2.2" 0" โ„๏ธ Dormant
Nov โ€” 1.8" 0" โ„๏ธ Dormant
Dec โ€” 1.6" 0" โ„๏ธ Dormant

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

Scarlet Runner 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.

Scarlet Runner Beans needs ~752 GDD — county provides 1,462 GDD Excellent fit

Scarlet Runner Beans Planting Timeline โ€” Adams County, ND

Scarlet Runner Beans Planting Calendar

Activity When Date Range
Start Indoors March 12 Mar 12 โ€“ Mar 26
Transplant Outdoors June 4 Jun 4 โ€“ Jun 18
Direct Sow May 28 May 28 โ€“ Jun 18
Harvest August 6 Aug 6 โ€“ Sep 10

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors
April โ€”
May Direct Sow
June Transplant Outdoors Direct Sow
July โ€”
August 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 Only during dry spells

๐Ÿ“… Days to Maturity

60โ€“80 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 4a

๐Ÿ“† Growing Season

136 days in Adams County

Growing Tips for Scarlet Runner Beans in Adams County

Direct sow Scarlet Runner Beans outdoors after May 14 in Adams County when soil has warmed and frost danger has passed.

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

General growing tips

Provide tall trellising for vigorous vines. Direct sow after frost. Harvest pods young for snap beans or let mature for shelling beans. Tubers are perennial in mild climates.

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 Scarlet Runner Beans in Adams County, ND?

Adams County is in Zone 4a with an average last frost of May 14. Plan your Scarlet Runner Beans planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Adams County, ND?

Adams County, North Dakota is in USDA Hardiness Zone 4a. The average last spring frost is May 14 and first fall frost is September 27.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Adams County gardeners in Zone 4a 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 Adams County, ND. Local conditions may vary. Last updated: April 2026.