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When to Plant Fava Beans in Portage County, WI

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.

Portage County, Wisconsin is in USDA Zone 4b. The average last spring frost is May 5 and the first fall frost is October 6, giving you a growing season of approximately 154 days.

At an elevation of 1,008 feet, Portage County receives approximately 37.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81ยฐF, so choose short-season varieties of Fava Beans to ensure they mature before fall.

Portage County, WI (Zone 4b) Moderate season
154 days
Last Spring Frost May 5
154 growing days
First Fall Frost October 6

Portage County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (39 days to spare)
Start indoors: Mar 17 Transplant: Apr 28 🍅 Harvest: Jul 14 – Aug 25
Recommended (50%) ✓ Fits season (35 days to spare)
Start indoors: Mar 24 Transplant: May 5 🍅 Harvest: Jul 21 – Sep 1
Safe Start (90%) ✓ Fits season (34 days to spare)
Start indoors: Apr 7 Transplant: May 19 🍅 Harvest: Aug 4 – Sep 15

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
1.0″/week
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 452 gal / 100 sq ft
Drought risk

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

Fava Beans needs ~941 GDD — county provides 1,655 GDD Excellent fit

Fava Beans Planting Timeline โ€” Portage County, WI

Fava Beans Planting Calendar

Activity When Date Range
Start Indoors March 24 Mar 24 โ€“ Apr 7
Transplant Outdoors May 5 May 5 โ€“ May 19
Direct Sow April 28 Apr 28 โ€“ May 19
Fall Sowing July 14 Jul 14 โ€“ Jul 28
Harvest July 21 Jul 21 โ€“ Sep 1

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

75โ€“100 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 4b

Growing Season

154 days

Growing Tips for Portage County

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

Level Up Your Garden

Frequently Asked Questions

When should I plant Fava Beans in Portage County, WI?

Portage County is in Zone 4b with an average last frost of May 5. Plan your Fava Beans planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Portage County, WI?

Portage County, Wisconsin is in USDA Hardiness Zone 4b. The average last spring frost is May 5 and first fall frost is October 6.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Portage County gardeners in Zone 4b 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 Portage County, WI. Local conditions may vary. Last updated: April 2026.