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When to Plant Lima Beans in Bonner County, ID

Lima beans are a warm-season legume producing large, creamy beans with a buttery texture. Both bush and pole varieties are available, with pole types yielding more.

Bonner County, Idaho is in USDA Zone 5b. The average last spring frost is May 5 and the first fall frost is October 3, giving you a growing season of approximately 151 days.

At an elevation of 7,480 feet, Bonner County receives approximately 12.9 inches of rainfall annually with predominantly loam soil. Summer highs average 86ยฐF, providing good warmth for Lima Beans during the growing season. With low rainfall, drip irrigation is essential for growing Lima Beans successfully. Mulch heavily to conserve soil moisture.

Bonner County, ID (Zone 5b) Moderate season
151 days
Last Spring Frost May 5
151 growing days
First Fall Frost October 3

Bonner County Soil Profile

Soil Type

Loam

Soil pH

6.4-8.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (40 days to spare)
Transplant: Apr 28 🍅 Harvest: Jun 30 – Aug 11
Recommended (50%) ✓ Fits season (46 days to spare)
Transplant: May 5 🍅 Harvest: Jul 7 – Aug 18
Safe Start (90%) ✓ Fits season (41 days to spare)
Transplant: Jun 1 🍅 Harvest: Aug 3 – Sep 14

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
0.4″/week
You supply
0.8″/week
Watering frequency 2-3 times/week
Season total 1,034 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Lima Beans needs ~1,088 GDD — county provides 2,189 GDD Excellent fit

Lima Beans Planting Timeline โ€” Bonner County, ID

Lima Beans Planting Calendar

Activity When Date Range
Direct Sow May 12 May 12 โ€“ Jun 2
Harvest July 14 Jul 14 โ€“ Aug 25

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Direct Sow
June Direct Sow
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

60โ€“90 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 5b

Growing Season

151 days

Growing Tips for Bonner County

Direct sow after soil is thoroughly warm at 65F or above. Do not soak seeds before planting as they may crack. Harvest when pods are plump but still green for fresh limas.

Companion Planting

Good Companions

Avoid Planting Near

  • Onion
  • Garlic
  • Fennel

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Frequently Asked Questions

When should I plant Lima Beans in Bonner County, ID?

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

What planting zone is Bonner County, ID?

Bonner County, Idaho is in USDA Hardiness Zone 5b. The average last spring frost is May 5 and first fall frost is October 3.

๐ŸŒฑ

Plan Your Garden with Confidence

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