When to Plant Comfrey in Big Stone County, MN
Comfrey is a vigorous perennial herb valued as a dynamic accumulator of nutrients. Its leaves make excellent mulch, compost activator, and liquid fertilizer.
Big Stone County, Minnesota is in USDA Zone 4a. The average last spring frost is May 2 and the first fall frost is October 4, giving you a growing season of approximately 155 days.
At an elevation of 823 feet, Big Stone County receives approximately 32.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Comfrey to ensure they mature before fall.
Big Stone County Soil Profile
Soil Type
Silt Loam
Soil pH
6.1-7.3
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 Big Stone County
How your county's soil matches Comfrey's growing requirements.
Soil pH
Your soil pH (6.1–7.3) overlaps with Comfrey's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Big Stone County is excellent for Comfrey — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Comfrey.
Organic Matter
Organic matter is excellent (4.5%) — Comfrey will thrive.
How to Plant Comfrey
Succession Planting Comfrey
Sow every 6.9 weeks. Last sowing by Jul 06 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Comfrey Planting Timeline — Big Stone County, MN
Comfrey Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 9 | May 9 – May 23 |
| Harvest | July 11 | Jul 11 – Sep 19 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | Harvest |
| August | Harvest |
| September | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · 1-2 times/week
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 4a
📆 Growing Season
155 days in Big Stone County
Growing Tips for Comfrey in Big Stone County
Direct sow Comfrey outdoors after May 02 in Big Stone County when soil has warmed and frost danger has passed.
General growing tips
Plant root cuttings 2 inches deep. Choose Bocking 14 variety to prevent self-seeding. Cut leaves 3-4 times per season for mulch or compost. Avoid planting near pathways as it spreads.
Companion Planting
Good Companions
Level Up Your Garden
Comfrey in Other Locations
Frequently Asked Questions
When should I plant Comfrey in Big Stone County, MN?
Big Stone County is in Zone 4a with an average last frost of May 2. Plan your Comfrey planting based on this frost date — see the calendar above for exact timing.
What planting zone is Big Stone County, MN?
Big Stone County, Minnesota is in USDA Hardiness Zone 4a. The average last spring frost is May 2 and first fall frost is October 4.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Big Stone County gardeners in Zone 4a organize planting dates, track what's growing, and never miss a planting window.
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