When to plant Comfrey in Iron County, MO
Plant Comfrey in Iron County during the brief April 23–May 7 window. With 188 frost-free days, fall plantings can't mature before October 21.
When to Plant Comfrey in Iron County, MO
Top priorities for Iron County, Missouri gardeners in June
If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.
-
It's harvest week for comfrey
The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.
Get ahead of July
- First harvests: comfrey
Comfrey is a vigorous perennial herb valued as a dynamic accumulator of nutrients. Its leaves make excellent mulch, compost activator, and liquid fertilizer.
Iron County, Missouri is in USDA Zone 6b. The average last spring frost is April 16 and the first fall frost is October 21, giving you a growing season of approximately 188 days.
At an elevation of 1,227 feet, Iron County receives approximately 35.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Comfrey during the growing season.
Iron County Soil Profile
Soil Type
Silt Loam
Soil pH
5.6-6.7
Drainage
Well Drained
Comfrey 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 Iron County
How your county's soil matches Comfrey's growing requirements.
Soil pH
Your soil pH (5.6–6.7) overlaps with Comfrey's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Iron County is excellent for Comfrey — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Comfrey.
Organic Matter
Organic matter is moderate (3.1%). Annual compost additions will help Comfrey.
How to Plant Comfrey
Succession Planting Comfrey
Sow every 6.9 weeks. Last sowing by Jul 23 to harvest before frost.
Comfrey Water Budget
Monthly Watering Guide for Comfrey
Comfrey needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Comfrey Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| May | 4.3" | 4" | 0.3" | 💧 Light watering |
| Jun | 4.3" | 4" | 0.3" | 💧 Light watering |
| Jul | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Aug | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Sep | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| Oct | 4.3" | 3.1" | 1.2" | 💧 Light watering |
| Nov | — | 2.5" | 0" | ❄️ Dormant |
| Dec | — | 2.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Iron County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Comfrey Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Comfrey Planting Timeline — Iron County, MO
Comfrey Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | April 23 | Apr 23 – May 7 |
| Harvest | June 25 | Jun 25 – Sep 3 |
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 | Harvest |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
188 days in Iron County
Growing Tips for Comfrey in Iron County
Direct sow Comfrey outdoors after April 16 in Iron 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
Check more plant combinations with our Companion Planting Checker →
Comfrey in Other Locations
Frequently Asked Questions
When should I plant Comfrey in Iron County, MO?
Iron County is in Zone 6b with an average last frost of April 16. Plan your Comfrey planting based on this frost date — see the calendar above for exact timing.
What planting zone is Iron County, MO?
Iron County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 16 and first fall frost is October 21.
When should I plant Comfrey in Iron County, MO?
In Iron County, MO, plant Comfrey after the last frost (around April 16) and before the first frost (around October 21). Best results when soil holds above 50°F.
What growing zone is Iron County, MO for Comfrey?
Iron County sits in USDA Zone 6b. Comfrey grows reliably in zones 3a through 9b, so it's a good fit here.
Can Comfrey grow in Iron County's climate?
Yes — Comfrey grows well in Iron County's temperate climate. Iron County averages a 188-day frost-free season, with last frost around April 16 and first frost around October 21.
Your Iron County Garden Planner — Free
A 22-page printable planner built for Iron County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.