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When to Plant Blueberries in Massac County, IL

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.

Massac County, Illinois is in USDA Zone 6b. The average last spring frost is April 7 and the first fall frost is October 21, giving you a growing season of approximately 197 days.

At an elevation of 778 feet, Massac County receives approximately 36 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86ยฐF, providing good warmth for Blueberries during the growing season.

Massac County, IL (Zone 6b) Moderate season
197 days
Last Spring Frost April 7
197 growing days
First Fall Frost October 21

Massac County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Apr 24
Recommended (50%) ✓ Fits season
Transplant: Apr 28
Safe Start (90%) ✓ Fits season
Transplant: May 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
1.0″/week
Rainfall provides
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 408 gal / 100 sq ft
Blueberries needs ~13,231 GDD — county provides 2,856 GDD May not mature

Blueberries Planting Timeline โ€” Massac County, IL

Blueberries Planting Calendar

Activity When Date Range
Transplant Outdoors April 28 Apr 28 โ€“ May 12

ยท 48" apart ยท Rows 72" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April Transplant Outdoors
May Transplant Outdoors
June โ€”
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 6b

Growing Season

197 days

Growing Tips for Massac 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 Massac County, IL?

Massac County is in Zone 6b with an average last frost of April 7. Plan your Blueberries planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Massac County, IL?

Massac County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 7 and first fall frost is October 21.

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Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Massac County gardeners in Zone 6b 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 Massac County, IL. Local conditions may vary. Last updated: April 2026.