When to Plant Black Beans in Franklin County, IL
Your May game plan for Franklin County, Illinois
We've pulled the most time-sensitive tasks for Franklin County, Illinois this May and put them front and centre. Tackle them in order.
Black beans are a warm-season legume producing small, dark, protein-rich beans that are a staple in Latin American and Caribbean cuisines.
Franklin County, Illinois is in USDA Zone 7a. The average last spring frost is April 10 and the first fall frost is October 20, giving you a growing season of approximately 193 days.
At an elevation of 747 feet, Franklin County receives approximately 37.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Black Beans during the growing season.
Franklin County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-7.1
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.
Soil Compatibility in Franklin County
How your county's soil matches Black Beans's growing requirements.
Soil pH
Your soil pH (5.9–7.1) overlaps with Black Beans's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Franklin County is excellent for Black Beans — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.3%) — Black Beans will thrive.
How to Plant Black Beans
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.7" | 0" | ❄️ Dormant |
| Mar | — | 2.7" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| May | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Aug | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Sep | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| Oct | 4.3" | 3.1" | 1.2" | 💧 Light watering |
| Nov | — | 2.6" | 0" | ❄️ Dormant |
| Dec | — | 2.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Franklin County). Supplement amounts are based on average rainfall — 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" — 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.
Black Beans Planting Timeline — Franklin County, IL
Black Beans Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | April 17 | Apr 17 – May 8 |
| Harvest | July 17 | Jul 17 – Sep 4 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Direct Sow |
| May | Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
90–120 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 7a
📆 Growing Season
193 days in Franklin County
Growing Tips for Black Beans in Franklin County
Direct sow Black Beans outdoors after April 10 in Franklin 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.
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
Check more plant combinations with our Companion Planting Checker →
Black Beans in Other Locations
Frequently Asked Questions
When should I plant Black Beans in Franklin County, IL?
Franklin County is in Zone 7a with an average last frost of April 10. Plan your Black Beans planting based on this frost date — see the calendar above for exact timing.
What planting zone is Franklin County, IL?
Franklin County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 10 and first fall frost is October 20.
Your Franklin County Garden Planner — Free
A 24-page printable planner built for Franklin County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.