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When to Plant Scarlet Runner Beans in Butler County, IA

Butler County, Iowa Zone 5a April

Your April gardening checklist

We've pulled the most time-sensitive tasks for Butler County, Iowa this April and put them front and centre. Tackle them in order.

Avg. last frost April 30
Avg. first frost October 7
Soil temp (4") 42°F
Watering Low
Pest pressure Low
Daylight 13.2 hrs
Get ahead of May
  • Transplants going out: scarlet runner beans
  • Direct-sowing: scarlet runner beans

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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.

Butler County, Iowa is in USDA Zone 5a. The average last spring frost is April 30 and the first fall frost is October 7, giving you a growing season of approximately 160 days.

At an elevation of 677 feet, Butler County receives approximately 39 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Scarlet Runner Beans to ensure they mature before fall.

Butler County, IA (Zone 5a) Moderate season
160 days
Last Spring Frost April 30
160 growing days
First Fall Frost October 7

Butler County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (49 days to spare)
Start indoors: Feb 27 Transplant: May 8 🍅 Harvest: Jul 10 – Aug 14
Recommended (50%) ✓ Fits season (48 days to spare)
Start indoors: Mar 5 Transplant: May 14 🍅 Harvest: Jul 16 – Aug 20
Safe Start (90%) ✓ Fits season (44 days to spare)
Start indoors: Mar 18 Transplant: May 27 🍅 Harvest: Jul 29 – Sep 2

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 Butler County

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

Soil pH

Your soil pH (5.8–7.2) overlaps with Scarlet Runner Beans's range (6.0–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Butler County is excellent for Scarlet Runner Beans — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.9%) — Scarlet Runner Beans will thrive.

How to Plant Scarlet Runner Beans

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

Succession Planting Scarlet Runner Beans

3
successive plantings in your 160-day season

Sow every 6.9 weeks. Last sowing by Jul 19 to harvest before frost.

Plant Water Budget

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

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 1.5" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 4.3" 4.1" 0.2" 💧 Light watering
May 4.3" 4.4" 0" ✅ Rainfall sufficient
Jun 4.3" 5.4" 0" ✅ Rainfall sufficient
Jul 4.3" 3.9" 0.4" 💧 Light watering
Aug 4.3" 4.8" 0" ✅ Rainfall sufficient
Sep 4.3" 3.4" 0.9" 💧 Light watering
Oct 4.3" 2.7" 1.6" 💧 Light watering
Nov 2.3" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Butler County). Supplement amounts are based on average rainfall — 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" — every day above 50°F 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 ~805 GDD — county provides 1,840 GDD Excellent fit

Scarlet Runner Beans Planting Timeline — Butler County, IA

Scarlet Runner Beans Planting Calendar

Activity When Date Range
Start Indoors March 5 Mar 5 – Mar 19
Transplant Outdoors May 14 May 14 – May 28
Direct Sow May 7 May 7 – May 28
Harvest July 16 Jul 16 – Aug 20

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

60–80 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 5a

📆 Growing Season

160 days in Butler County

Growing Tips for Scarlet Runner Beans in Butler County

Direct sow Scarlet Runner Beans outdoors after April 30 in Butler 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 Butler County, IA?

Butler County is in Zone 5a with an average last frost of April 30. Plan your Scarlet Runner Beans planting based on this frost date — see the calendar above for exact timing.

What planting zone is Butler County, IA?

Butler County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 30 and first fall frost is October 7.

🌱

Your Butler County Garden Planner — Free

A 24-page printable planner built for Butler County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Butler County, IA. Local conditions may vary. Last updated: April 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.