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When to Plant Blueberries in St. Louis City, MO

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.

St. Louis City, Missouri is in USDA Zone 6b. The average last spring frost is April 8 and the first fall frost is October 27, giving you a growing season of approximately 202 days.

At an elevation of 612 feet, St. Louis City receives approximately 40.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91ยฐF, providing good warmth for Blueberries during the growing season.

St. Louis City, MO (Zone 6b) Long season
202 days
Last Spring Frost April 8
202 growing days
First Fall Frost October 27

St. Louis City Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: Apr 21
Recommended (50%) ✓ Fits season
Transplant: Apr 29
Safe Start (90%) ✓ Fits season
Transplant: May 11

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
0.9″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 327 gal / 100 sq ft
Drought risk

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

Blueberries needs ~16,653 GDD — county provides 3,686 GDD May not mature

Blueberries Planting Timeline โ€” St. Louis City, MO

Blueberries Planting Calendar

Activity When Date Range
Transplant Outdoors April 29 Apr 29 โ€“ May 13

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

202 days

Growing Tips for St. Louis City

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 St. Louis City, MO?

St. Louis City is in Zone 6b with an average last frost of April 8. Plan your Blueberries planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is St. Louis City, MO?

St. Louis City, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 8 and first fall frost is October 27.

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Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help St. Louis City 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 St. Louis City, MO. Local conditions may vary. Last updated: April 2026.