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When to Plant Fava Beans in DeKalb County, MO

Fava beans are a cool-season legume with large, meaty beans inside thick pods. They fix nitrogen in the soil and are one of the oldest cultivated crops.

DeKalb County, Missouri is in USDA Zone 5b. The average last spring frost is April 14 and the first fall frost is October 18, giving you a growing season of approximately 187 days.

At an elevation of 917 feet, DeKalb County receives approximately 39 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87ยฐF, providing good warmth for Fava Beans during the growing season.

DeKalb County, MO (Zone 5b) Moderate season
187 days
Last Spring Frost April 14
187 growing days
First Fall Frost October 18

DeKalb County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (65 days to spare)
Start indoors: Mar 6 Transplant: Apr 10 🍅 Harvest: Jun 26 – Aug 7
Recommended (50%) ✓ Fits season (68 days to spare)
Start indoors: Mar 10 Transplant: Apr 14 🍅 Harvest: Jun 30 – Aug 11
Safe Start (90%) ✓ Fits season (65 days to spare)
Start indoors: Mar 26 Transplant: Apr 30 🍅 Harvest: Jul 16 – Aug 27

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 DeKalb County

How your county's soil matches Fava Beans's growing requirements.

Soil pH

Your soil pH (5.5โ€“7.1) overlaps with Fava Beans's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

The silt loam soil in DeKalb County is excellent for Fava Beans โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.8%). Annual compost additions will help Fava Beans.

How to Plant Fava Beans

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

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Fava Beans

2
successive plantings in your 187-day season

Sow every 8.6 weeks. Last sowing by Jul 10 to harvest before frost.

For a dedicated fall crop, sow by Aug 09.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 206 gal / 100 sq ft

Monthly Watering Guide for Fava Beans

Fava 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 Fava Beans Needs Rainfall You Supplement Action
Jan โ€” 1.6" 0" โ„๏ธ Dormant
Feb โ€” 1.6" 0" โ„๏ธ Dormant
Mar โ€” 2.9" 0" โ„๏ธ Dormant
Apr 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
May 4.3" 3.9" 0.4" ๐Ÿ’ง Light watering
Jun 4.3" 4.9" 0" โœ… Rainfall sufficient
Jul 4.3" 4.9" 0" โœ… Rainfall sufficient
Aug 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Sep 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Oct 4.3" 3.1" 1.2" ๐Ÿ’ง Light watering
Nov โ€” 2.6" 0" โ„๏ธ Dormant
Dec โ€” 2.2" 0" โ„๏ธ Dormant

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

Fava 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.

Fava Beans needs ~1,334 GDD — county provides 2,851 GDD Excellent fit

Fava Beans Planting Timeline โ€” DeKalb County, MO

Fava Beans Planting Calendar

Activity When Date Range
Start Indoors March 10 Mar 10 โ€“ Mar 24
Transplant Outdoors April 14 Apr 14 โ€“ Apr 28
Direct Sow March 31 Mar 31 โ€“ Apr 21
Harvest June 30 Jun 30 โ€“ Aug 11
Fall Sowing August 9 Aug 9 โ€“ Aug 23

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

Month-by-Month Timeline

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

75โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 5b

๐Ÿ“† Growing Season

187 days in DeKalb County

Growing Tips for Fava Beans in DeKalb County

Direct sow Fava Beans outdoors after April 14 in DeKalb County when soil has warmed and frost danger has passed.

Common pests for Fava 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 as early as soil can be worked in spring. Pinch growing tips when pods begin to form to redirect energy and reduce aphid problems. Stake tall varieties.

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 Fava Beans in DeKalb County, MO?

DeKalb County is in Zone 5b with an average last frost of April 14. Plan your Fava Beans planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is DeKalb County, MO?

DeKalb County, Missouri is in USDA Hardiness Zone 5b. The average last spring frost is April 14 and first fall frost is October 18.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help DeKalb 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 DeKalb County, MO. Local conditions may vary. Last updated: April 2026.