When to Plant Comfrey in Boone County, MO
Comfrey is a vigorous perennial herb valued as a dynamic accumulator of nutrients. Its leaves make excellent mulch, compost activator, and liquid fertilizer.
Boone County, Missouri is in USDA Zone 6a. The average last spring frost is April 10 and the first fall frost is October 25, giving you a growing season of approximately 198 days.
At an elevation of 727 feet, Boone County receives approximately 33.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Comfrey during the growing season.
Boone County Soil Profile
Soil Type
Silt Loam
Soil pH
5.6-7.1
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
Comfrey Planting Timeline — Boone County, MO
Comfrey Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 17 | Apr 17 – May 1 |
| Harvest | June 19 | Jun 19 – Aug 28 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Transplant Outdoors |
| May | Transplant Outdoors |
| June | Harvest |
| July | Harvest |
| August | Harvest |
| September | — |
| 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 6a
Growing Season
198 days
Growing Tips for Boone 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 Boone County, MO?
Boone County is in Zone 6a with an average last frost of April 10. Plan your Comfrey planting based on this frost date — see the calendar above for exact timing.
What planting zone is Boone County, MO?
Boone County, Missouri is in USDA Hardiness Zone 6a. The average last spring frost is April 10 and first fall frost is October 25.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Boone County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.
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