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When to Plant Lingonberries in Delaware County, IA

Lingonberries are low-growing evergreen shrubs producing small, tart red berries used in Scandinavian cuisine. They thrive in acidic soil and cold climates.

Delaware County, Iowa is in USDA Zone 4b. The average last spring frost is May 2 and the first fall frost is October 7, giving you a growing season of approximately 158 days.

At an elevation of 974 feet, Delaware County receives approximately 31.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83ยฐF, so choose short-season varieties of Lingonberries to ensure they mature before fall.

Delaware County, IA (Zone 4b) Moderate season
158 days
Last Spring Frost May 2
158 growing days
First Fall Frost October 7

Delaware County Soil Profile

Soil Type

Silt Loam

Soil pH

6-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: May 23
Recommended (50%) ✓ Fits season
Transplant: May 30
Safe Start (90%) ✓ Fits season
Transplant: Jun 13

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 236 gal / 100 sq ft
Lingonberries needs ~11,178 GDD — county provides 1,935 GDD May not mature

Lingonberries Planting Timeline โ€” Delaware County, IA

Lingonberries Planting Calendar

Activity When Date Range
Transplant Outdoors May 30 May 30 โ€“ Jun 13

ยท 48" apart ยท Rows 72" apart

Month-by-Month Timeline

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

Growing Conditions

Sun

Partial Shade (3-6 hours)

Water

Moderate โ€” regular watering

Days to Maturity

730โ€“1095 days

Soil pH

4.5 โ€“ 5.5

USDA Zone

Zone 4b

Growing Season

158 days

Growing Tips for Delaware County

Amend soil with peat and pine needle mulch for acidity. Plant 12 inches apart as a ground cover. Berries ripen in late summer. Requires minimal pruning.

Companion Planting

Good Companions

Level Up Your Garden

Frequently Asked Questions

When should I plant Lingonberries in Delaware County, IA?

Delaware County is in Zone 4b with an average last frost of May 2. Plan your Lingonberries planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Delaware County, IA?

Delaware County, Iowa is in USDA Hardiness Zone 4b. The average last spring frost is May 2 and first fall frost is October 7.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Delaware County gardeners in Zone 4b 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 Delaware County, IA. Local conditions may vary. Last updated: April 2026.