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When to Plant Blueberries in Washburn County, WI

Blueberries are long-lived shrubs producing sweet, antioxidant-rich berries. They require acidic soil and are attractive ornamental plants with fall color and spring flowers.

Washburn County, Wisconsin is in USDA Zone 3b. The average last spring frost is May 17 and the first fall frost is September 25, giving you a growing season of approximately 131 days.

At an elevation of 954 feet, Washburn County receives approximately 32.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 79ยฐF, so choose short-season varieties of Blueberries to ensure they mature before fall.

Washburn County, WI (Zone 3b) Short season
131 days
Last Spring Frost May 17
131 growing days
First Fall Frost September 25

Washburn County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-6.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Jun 11
Recommended (50%) ✓ Fits season
Transplant: Jun 14
Safe Start (90%) ✓ Fits season
Transplant: Jun 29

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
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

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

Blueberries needs ~8,441 GDD — county provides 1,211 GDD May not mature

Blueberries Planting Timeline โ€” Washburn County, WI

Blueberries Planting Calendar

Activity When Date Range
Transplant Outdoors June 14 Jun 14 โ€“ Jun 28

ยท 48" apart ยท Rows 72" 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

Moderate โ€” regular watering

Days to Maturity

730โ€“1095 days

Soil pH

4.5 โ€“ 5.5

USDA Zone

Zone 3b

Growing Season

131 days

Growing Tips for Washburn County

Plant at least two varieties for cross-pollination. Acidify soil with sulfur or pine needle mulch to maintain pH 4.5-5.5. Protect ripening berries from birds with netting.

Companion Planting

Good Companions

Level Up Your Garden

Frequently Asked Questions

When should I plant Blueberries in Washburn County, WI?

Washburn County is in Zone 3b with an average last frost of May 17. Plan your Blueberries planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Washburn County, WI?

Washburn County, Wisconsin is in USDA Hardiness Zone 3b. The average last spring frost is May 17 and first fall frost is September 25.

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Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Washburn County gardeners in Zone 3b organize planting dates, track what's growing, and never miss a planting window.

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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 Washburn County, WI. Local conditions may vary. Last updated: April 2026.