When to Plant Comfrey in Allegheny County, PA
Comfrey is a vigorous perennial herb valued as a dynamic accumulator of nutrients. Its leaves make excellent mulch, compost activator, and liquid fertilizer.
Allegheny County, Pennsylvania is in USDA Zone 6a. The average last spring frost is April 25 and the first fall frost is October 28, giving you a growing season of approximately 186 days.
At an elevation of 118 feet, Allegheny County receives approximately 40.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Comfrey during the growing season.
Allegheny County Soil Profile
Soil Type
Silt Loam
Soil pH
5-6.5
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 — Allegheny County, PA
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 6a
Growing Season
186 days
Growing Tips for Allegheny 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 Allegheny County, PA?
Allegheny County is in Zone 6a 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 Allegheny County, PA?
Allegheny County, Pennsylvania is in USDA Hardiness Zone 6a. The average last spring frost is April 25 and first fall frost is October 28.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Allegheny County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.
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