Blog

When to plant Comfrey in Dallas County, IA

Dallas County's 168-day season only supports one Comfrey planting per year. Sow between May 1 and May 15 for the best chance at full maturity before October 9.

When to Plant Comfrey in Dallas 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.

Dallas County, Iowa is in USDA Zone 5b. The average last spring frost is April 24 and the first fall frost is October 9, giving you a growing season of approximately 168 days.

At an elevation of 693 feet, Dallas County receives approximately 37.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Comfrey during the growing season.

Dallas County, IA (Zone 5b) Moderate season
168 days
Last Spring Frost April 24
168 growing days
First Fall Frost October 9

Dallas County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7

Drainage

Well Drained

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 1.8" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 4.3" 3.6" 0.7" 💧 Light watering
May 4.3" 3.9" 0.4" 💧 Light watering
Jun 4.3" 4.8" 0" ✅ Rainfall sufficient
Jul 4.3" 4.3" 0" ✅ Rainfall sufficient
Aug 4.3" 4.5" 0" ✅ Rainfall sufficient
Sep 4.3" 3.6" 0.7" 💧 Light watering
Oct 4.3" 2.7" 1.6" 💧 Light watering
Nov 2.4" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Dallas County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Comfrey Planting Timeline — Dallas County, IA

Comfrey Planting Calendar

Activity When Date Range
Transplant Outdoors May 1 May 1 – May 15
Harvest July 3 Jul 3 – Sep 11

Plant 0.5" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
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

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5b

📆 Growing Season

168 days in Dallas County

Growing Tips for Dallas 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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Comfrey in Dallas County, IA?

Dallas County is in Zone 5b with an average last frost of April 24. Plan your Comfrey planting based on this frost date — see the calendar above for exact timing.

What planting zone is Dallas County, IA?

Dallas County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 24 and first fall frost is October 9.

When should I plant Comfrey in Dallas County, IA?

In Dallas County, IA, plant Comfrey after the last frost (around April 24) and before the first frost (around October 9). Best results when soil holds above 50°F.

What growing zone is Dallas County, IA for Comfrey?

Dallas County sits in USDA Zone 5b. Comfrey grows reliably in zones 3a through 9b, so it's a good fit here.

Can Comfrey grow in Dallas County's climate?

Yes — Comfrey grows well in Dallas County's temperate climate. Dallas County averages a 168-day frost-free season, with last frost around April 24 and first frost around October 9.

🌱

Your Dallas County Garden Planner — Free

A 22-page printable planner built for Dallas County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Dallas County, IA. Local conditions may vary. Last updated: July 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.