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When to Plant Pole Beans in Cass County, IL

Pole beans are climbing varieties of green beans that produce over a much longer season than bush types. They require trellising but yield more per square foot.

Cass County, Illinois is in USDA Zone 5b. The average last spring frost is April 15 and the first fall frost is October 16, giving you a growing season of approximately 184 days.

At an elevation of 703 feet, Cass County receives approximately 31.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83ยฐF, so choose short-season varieties of Pole Beans to ensure they mature before fall.

Cass County, IL (Zone 5b) Moderate season
184 days
Last Spring Frost April 15
184 growing days
First Fall Frost October 16

Cass County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (58 days to spare)
Start indoors: Feb 12 Transplant: Apr 23 🍅 Harvest: Jun 18 – Aug 13
Recommended (50%) ✓ Fits season (58 days to spare)
Start indoors: Feb 18 Transplant: Apr 29 🍅 Harvest: Jun 24 – Aug 19
Safe Start (90%) ✓ Fits season (56 days to spare)
Start indoors: Mar 5 Transplant: May 14 🍅 Harvest: Jul 9 – Sep 3

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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.7″/week
Watering frequency 1-2 times/week
Season total 1,124 gal / 100 sq ft
Drought risk

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

Pole Beans needs ~766 GDD — county provides 2,254 GDD Excellent fit

Pole Beans Planting Timeline โ€” Cass County, IL

Pole Beans Planting Calendar

Activity When Date Range
Start Indoors February 18 Feb 18 โ€“ Mar 4
Transplant Outdoors April 29 Apr 29 โ€“ May 13
Direct Sow April 22 Apr 22 โ€“ May 13
Harvest June 24 Jun 24 โ€“ Aug 19

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

55โ€“70 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 5b

Growing Season

184 days

Growing Tips for Cass County

Provide sturdy 6-8 foot poles, tepees, or trellises. Direct sow after last frost. Pick regularly to encourage continued production. Beans fix nitrogen benefiting following crops.

Companion Planting

Good Companions

Avoid Planting Near

  • Onion
  • Garlic
  • Fennel

Level Up Your Garden

Frequently Asked Questions

When should I plant Pole Beans in Cass County, IL?

Cass County is in Zone 5b with an average last frost of April 15. Plan your Pole Beans planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Cass County, IL?

Cass County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 15 and first fall frost is October 16.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Cass County gardeners in Zone 5b 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 Cass County, IL. Local conditions may vary. Last updated: April 2026.