When to Plant Comfrey in Sac County, IA
Comfrey is a vigorous perennial herb valued as a dynamic accumulator of nutrients. Its leaves make excellent mulch, compost activator, and liquid fertilizer.
Sac County, Iowa is in USDA Zone 4b. The average last spring frost is April 25 and the first fall frost is October 8, giving you a growing season of approximately 166 days.
At an elevation of 1,221 feet, Sac County receives approximately 31.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Comfrey to ensure they mature before fall.
Sac County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-6.7
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 6/10 — consider drought-tolerant varieties and mulching
Comfrey Planting Timeline — Sac County, IA
Comfrey Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | May 2 | May 2 – May 16 |
| Harvest | July 4 | Jul 4 – Sep 12 |
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
Moderate — regular watering
Days to Maturity
60–90 days
Soil pH
6 – 7
USDA Zone
Zone 4b
Growing Season
166 days
Growing Tips for Sac County
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 Sac County, IA?
Sac County is in Zone 4b with an average last frost of April 25. Plan your Comfrey planting based on this frost date — see the calendar above for exact timing.
What planting zone is Sac County, IA?
Sac County, Iowa is in USDA Hardiness Zone 4b. The average last spring frost is April 25 and first fall frost is October 8.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Sac County gardeners in Zone 4b organize planting dates, track what's growing, and never miss a planting window.
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