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When to Plant Cranberries in Bonneville County, ID

Cranberries are low-growing, vine-like shrubs that produce tart red berries in fall. They grow in acidic, boggy conditions and are surprisingly easy to cultivate.

Bonneville County, Idaho is in USDA Zone 5a. The average last spring frost is May 26 and the first fall frost is September 19, giving you a growing season of approximately 116 days.

At an elevation of 7,993 feet, Bonneville County receives approximately 20.9 inches of rainfall annually with predominantly loam soil. Summer highs average 85ยฐF, providing good warmth for Cranberries during the growing season.

Bonneville County, ID (Zone 5a) Short season
116 days
Last Spring Frost May 26
116 growing days
First Fall Frost September 19

Bonneville County Soil Profile

Soil Type

Loam

Soil pH

6.5-8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Jun 3
Recommended (50%) ✓ Fits season
Transplant: Jun 16
Safe Start (90%) ✓ Fits season
Transplant: Jul 12

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
1.5″/week
Rainfall provides
0.8″/week
You supply
0.9″/week
Watering frequency 2-3 times/week
Season total 921 gal / 100 sq ft
Drought risk

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

Cranberries needs ~12,547 GDD — county provides 1,595 GDD May not mature

Cranberries Planting Timeline โ€” Bonneville County, ID

Cranberries Planting Calendar

Activity When Date Range
Transplant Outdoors June 16 Jun 16 โ€“ Jun 30

ยท 36" apart ยท Rows 48" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May โ€”
June Transplant Outdoors
July โ€”
August โ€”
September โ€”
October โ€”
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

High โ€” keep soil consistently moist

Days to Maturity

730โ€“1095 days

Soil pH

4 โ€“ 5.5

USDA Zone

Zone 5a

Growing Season

116 days

Growing Tips for Bonneville County

Create an acidic, consistently moist bed with peat moss. Cranberries do not need to be flooded to grow; flooding is only used for commercial harvesting. Mulch with sand in early spring.

Companion Planting

Good Companions

Level Up Your Garden

Frequently Asked Questions

When should I plant Cranberries in Bonneville County, ID?

Bonneville County is in Zone 5a with an average last frost of May 26. Plan your Cranberries planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Bonneville County, ID?

Bonneville County, Idaho is in USDA Hardiness Zone 5a. The average last spring frost is May 26 and first fall frost is September 19.

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Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Bonneville County gardeners in Zone 5a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Bonneville County, ID. Local conditions may vary. Last updated: April 2026.