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When to plant Blueberries in Clay County, IL

Plant Blueberries in Clay County during the brief May 5–May 19 window. With 186 frost-free days, fall plantings can't mature before October 17.

When to Plant Blueberries in Clay County, IL

Blueberries

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.

Clay County, Illinois is in USDA Zone 6b. The average last spring frost is April 14 and the first fall frost is October 17, giving you a growing season of approximately 186 days.

At an elevation of 1,105 feet, Clay County receives approximately 34.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Blueberries during the growing season.

Clay County, IL (Zone 6b) Moderate season
186 days
Last Spring Frost April 14
186 growing days
First Fall Frost October 17

Clay County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

How Much Blueberries to Grow

5-10 lbs
Average yield per plant
2
Plants per person
4 sq ft
Space per person

For a family of 4, plant approximately 8 blueberries plants in about 16 sq ft. In Clay County's 186-day season, you'll have plenty of time for a full harvest. Plan your garden layout →

Blueberries Planting Timeline — Clay County, IL

Blueberries Planting Calendar

Activity When Date Range
Transplant Outdoors May 5 May 5 – May 19

· 48" apart · Rows 72" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

730–1095 days

🧪 Soil pH

Needs 4.5–5.5 · Your soil: N/A

🗺️ USDA Zone

Zone 6b

📆 Growing Season

186 days in Clay County

Growing Tips for Clay 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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Blueberries in Clay County, IL?

Clay County is in Zone 6b with an average last frost of April 14. Plan your Blueberries planting based on this frost date — see the calendar above for exact timing.

What planting zone is Clay County, IL?

Clay County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 14 and first fall frost is October 17.

When should I plant Blueberries in Clay County, IL?

In Clay County, IL, plant Blueberries after the last frost (around April 14) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is Clay County, IL for Blueberries?

Clay County sits in USDA Zone 6b. Blueberries grows reliably in zones 3a through 8b, so it's a good fit here.

Can Blueberries grow in Clay County's climate?

Yes — Blueberries grows well in Clay County's temperate climate. Clay County averages a 186-day frost-free season, with last frost around April 14 and first frost around October 17.

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Your Clay County Garden Planner — Free

A 22-page printable planner built for Clay County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

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