When to Plant Lingonberries in Cass County, IL
Lingonberries are low-growing evergreen shrubs producing small, tart red berries used in Scandinavian cuisine. They thrive in acidic soil and cold climates.
Cass County, Illinois is in USDA Zone 5b. The average last spring frost is April 15 and the first fall frost is October 16, giving you a growing season of approximately 184 days.
At an elevation of 703 feet, Cass County receives approximately 31.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Lingonberries to ensure they mature before fall.
Cass County Soil Profile
Soil Type
Silt Loam
Soil pH
6-7.2
Drainage
Well Drained
Plant Planting Risk Windows
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.
Soil Compatibility in Cass County
How your county's soil matches Lingonberries's growing requirements.
Soil pH
Your soil pH (6.0–7.2) is more alkaline than Lingonberries prefers (4.5–5.5). Add sulfur or peat moss to lower pH.
Soil Texture
The silt loam soil in Cass County is excellent for Lingonberries — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Lingonberries.
Organic Matter
Organic matter is moderate (4.0%). Annual compost additions will help Lingonberries.
How to Plant Lingonberries
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Lingonberries
Lingonberries needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Lingonberries Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| May | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Jun | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Jul | 4.3" | 3.3" | 1" | 💧 Light watering |
| Aug | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Sep | 4.3" | 3.3" | 1" | 💧 Light watering |
| Oct | 4.3" | 2.6" | 1.7" | 💧 Light watering |
| Nov | — | 2" | 0" | ❄️ Dormant |
| Dec | — | 1.6" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Cass County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Lingonberries Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Lingonberries Planting Timeline — Cass County, IL
Lingonberries Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 6 | May 6 – May 20 |
· 48" apart · Rows 72" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
730–1095 days
🧪 Soil pH
Needs 4.5–5.5 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 5b
📆 Growing Season
184 days in Cass County
Growing Tips for Lingonberries in Cass County
Direct sow Lingonberries outdoors after April 15 in Cass County when soil has warmed and frost danger has passed.
Your 184.0-day growing season in Cass County is tight for Lingonberries (730.0-1095.0 days to maturity). Start indoors and choose early-maturing varieties.
General growing tips
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
Check more plant combinations with our Companion Planting Checker →
Lingonberries in Other Locations
Frequently Asked Questions
When should I plant Lingonberries in Cass County, IL?
Cass County is in Zone 5b with an average last frost of April 15. Plan your Lingonberries planting based on this frost date — see the calendar above for exact timing.
What planting zone is Cass County, IL?
Cass County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 15 and first fall frost is October 16.
Plan Your Garden with Confidence
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