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When to Plant Lingonberries in Polk 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.

Polk County, Iowa is in USDA Zone 5a. 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 1,037 feet, Polk County receives approximately 30.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86ยฐF, providing good warmth for Lingonberries during the growing season.

Polk County, IA (Zone 5a) Moderate season
158 days
Last Spring Frost May 2
158 growing days
First Fall Frost October 7

Polk 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 13
Recommended (50%) ✓ Fits season
Transplant: May 23
Safe Start (90%) ✓ Fits season
Transplant: Jun 2

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
0.6″/week
Watering frequency 1-2 times/week
Season total 839 gal / 100 sq ft
Drought risk

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

Lingonberries needs ~13,231 GDD — county provides 2,291 GDD May not mature

Lingonberries Planting Timeline โ€” Polk County, IA

Lingonberries Planting Calendar

Activity When Date Range
Transplant Outdoors May 23 May 23 โ€“ Jun 6

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 5a

Growing Season

158 days

Growing Tips for Polk 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 Polk County, IA?

Polk County is in Zone 5a 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 Polk County, IA?

Polk County, Iowa is in USDA Hardiness Zone 5a. 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 Polk 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 Polk County, IA. Local conditions may vary. Last updated: April 2026.