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When to Plant Lingonberries in Union 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.

Union County, Iowa is in USDA Zone 5a. The average last spring frost is April 23 and the first fall frost is October 11, giving you a growing season of approximately 171 days.

At an elevation of 1,311 feet, Union County receives approximately 39 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.

Union County, IA (Zone 5a) Moderate season
171 days
Last Spring Frost April 23
171 growing days
First Fall Frost October 11

Union County Soil Profile

Soil Type

Silt Loam

Soil pH

6.3-7.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season
Transplant: May 8
Recommended (50%) ✓ Fits season
Transplant: May 14
Safe Start (90%) ✓ Fits season
Transplant: May 30

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
1.0″/week
You supply
0.0″/week
Watering frequency Only during dry spells
Season total 64 gal / 100 sq ft
Lingonberries needs ~11,178 GDD — county provides 2,094 GDD May not mature

Lingonberries Planting Timeline โ€” Union County, IA

Lingonberries Planting Calendar

Activity When Date Range
Transplant Outdoors May 14 May 14 โ€“ May 28

ยท 48" apart ยท Rows 72" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March โ€”
April โ€”
May Transplant Outdoors
June โ€”
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 5a

Growing Season

171 days

Growing Tips for Union 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 Union County, IA?

Union County is in Zone 5a with an average last frost of April 23. Plan your Lingonberries planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Union County, IA?

Union County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 23 and first fall frost is October 11.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Union County gardeners in Zone 5a 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 Union County, IA. Local conditions may vary. Last updated: April 2026.