When to Plant Yard Long Beans in Knox County, IL
Yard long beans are a tropical legume that produces slender pods up to 24 inches long. They are a staple in Southeast Asian cooking and thrive in hot weather.
Knox County, Illinois is in USDA Zone 5a. The average last spring frost is April 17 and the first fall frost is October 15, giving you a growing season of approximately 181 days.
At an elevation of 1,301 feet, Knox County receives approximately 33.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Yard Long Beans to ensure they mature before fall.
Knox County Soil Profile
Soil Type
Silt Loam
Soil pH
6-6.8
Drainage
Well Drained
Plant Planting Risk Windows
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
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Yard Long Beans Planting Timeline — Knox County, IL
Yard Long Beans Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 20 | Feb 20 – Mar 6 |
| Transplant Outdoors | May 1 | May 1 – May 15 |
| Direct Sow | April 24 | Apr 24 – May 15 |
| Harvest | June 26 | Jun 26 – Aug 7 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
55–80 days
Soil pH
6 – 7.5
USDA Zone
Zone 5a
Growing Season
181 days
Growing Tips for Knox County
Direct sow after soil is warm. Provide tall poles or trellising as vines can reach 8-10 feet. Harvest when pods are pencil-thick before seeds bulge. Cook quickly for best texture.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Yard Long Beans in Other Locations
Frequently Asked Questions
When should I plant Yard Long Beans in Knox County, IL?
Knox County is in Zone 5a with an average last frost of April 17. Plan your Yard Long Beans planting based on this frost date — see the calendar above for exact timing.
What planting zone is Knox County, IL?
Knox County, Illinois is in USDA Hardiness Zone 5a. The average last spring frost is April 17 and first fall frost is October 15.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Knox County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.
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