When to Plant Comfrey in Lake County, CA
Comfrey is a vigorous perennial herb valued as a dynamic accumulator of nutrients. Its leaves make excellent mulch, compost activator, and liquid fertilizer.
Lake County, California is in USDA Zone 8b. The average last spring frost is March 2 and the first fall frost is November 27, giving you a growing season of approximately 270 days.
At an elevation of 154 feet, Lake County receives approximately 30.4 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 83°F, so choose short-season varieties of Comfrey to ensure they mature before fall. Sandy soil warms quickly in spring — great for early planting — but Comfrey will need more frequent watering and organic matter to retain nutrients.
Lake County Soil Profile
Soil Type
Sandy Loam
Soil pH
6.1-6.9
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 Lake County
How your county's soil matches Comfrey's growing requirements.
Soil pH
Your soil pH (6.1–6.9) is within Comfrey's preferred range (6.0–7.0).
Soil Texture
Sandy soil in Lake County warms quickly in spring but drains fast. Comfrey will need more frequent watering and regular compost additions to retain nutrients.
Organic Matter
Organic matter is moderate (2.7%). Annual compost additions will help Comfrey.
How to Plant Comfrey
Succession Planting Comfrey
Sow every 6.9 weeks. Last sowing by Aug 29 to harvest before frost.
Plant 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 | — | 6.2" | 0" | ❄️ Dormant |
| Feb | — | 6.5" | 0" | ❄️ Dormant |
| Mar | 4.3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Apr | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| May | 4.3" | 0.8" | 3.5" | 🚿 Regular watering |
| Jun | 4.3" | 0.2" | 4.1" | 🚿 Regular watering |
| Jul | 4.3" | 0" | 4.3" | 🚿 Regular watering |
| Aug | 4.3" | 0" | 4.3" | 🚿 Regular watering |
| Sep | 4.3" | 0.3" | 4" | 🚿 Regular watering |
| Oct | 4.3" | 1.1" | 3.2" | 🚿 Regular watering |
| Nov | 4.3" | 3" | 1.3" | 💧 Light watering |
| Dec | — | 5.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Lake 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 — Lake County, CA
Comfrey Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | March 9 | Mar 9 – Mar 23 |
| Harvest | May 11 | May 11 – Jul 20 |
Plant 0.5" deep · 8" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Transplant Outdoors |
| April | — |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| 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: ideal
🗺️ USDA Zone
Zone 8b
📆 Growing Season
270 days in Lake County
Growing Tips for Comfrey in Lake County
Direct sow Comfrey outdoors after March 02 in Lake County when soil has warmed and frost danger has passed.
Sandy soil in Lake County dries quickly — mulch Comfrey with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
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 Lake County, CA?
Lake County is in Zone 8b with an average last frost of March 2. Plan your Comfrey planting based on this frost date — see the calendar above for exact timing.
What planting zone is Lake County, CA?
Lake County, California is in USDA Hardiness Zone 8b. The average last spring frost is March 2 and first fall frost is November 27.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Lake County gardeners in Zone 8b organize planting dates, track what's growing, and never miss a planting window.
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