When to Plant Cranberries in Carbon County, MT
Cranberries are low-growing, vine-like shrubs that produce tart red berries in fall. They grow in acidic, boggy conditions and are surprisingly easy to cultivate.
Carbon County, Montana is in USDA Zone 4b. The average last spring frost is May 13 and the first fall frost is September 28, giving you a growing season of approximately 138 days.
At an elevation of 5,849 feet, Carbon County receives approximately 23.3 inches of rainfall annually with predominantly loam soil. Summer highs average 83°F, so choose short-season varieties of Cranberries to ensure they mature before fall.
Carbon County Soil Profile
Soil Type
Loam
Soil pH
6.8-8.1
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.
Plant Water Budget
Water stress score is 8/10 — consider drought-tolerant varieties and mulching
Cranberries Planting Timeline — Carbon County, MT
Cranberries Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | June 10 | Jun 10 – Jun 24 |
· 36" apart · Rows 48" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | — |
| June | Transplant Outdoors |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
High — keep soil consistently moist
Days to Maturity
730–1095 days
Soil pH
4 – 5.5
USDA Zone
Zone 4b
Growing Season
138 days
Growing Tips for Carbon County
Create an acidic, consistently moist bed with peat moss. Cranberries do not need to be flooded to grow; flooding is only used for commercial harvesting. Mulch with sand in early spring.
Companion Planting
Good Companions
Level Up Your Garden
Cranberries in Other Locations
Frequently Asked Questions
When should I plant Cranberries in Carbon County, MT?
Carbon County is in Zone 4b with an average last frost of May 13. Plan your Cranberries planting based on this frost date — see the calendar above for exact timing.
What planting zone is Carbon County, MT?
Carbon County, Montana is in USDA Hardiness Zone 4b. The average last spring frost is May 13 and first fall frost is September 28.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Carbon County gardeners in Zone 4b organize planting dates, track what's growing, and never miss a planting window.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.