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When to plant Feverfew in Clarke County, IA

Plant Feverfew in Clarke County during the brief May 1–May 15 window. With 170 frost-free days, fall plantings can't mature before October 11.

When to Plant Feverfew in Clarke County, IA

Clarke County, Iowa Zone 5b June

Your June gardening checklist

Your Clarke County, Iowa garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.

Avg. last frost April 24
Avg. first frost October 11
Soil temp (4") 67°F
Watering Low
Pest pressure High
Daylight 14.9 hrs
To set up a strong July, finish these tasks
  • First harvests: feverfew

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Feverfew is a bushy perennial herb with small daisy-like flowers and aromatic leaves. It has been used traditionally for headache relief and is a cheerful garden plant.

Clarke County, Iowa is in USDA Zone 5b. The average last spring frost is April 24 and the first fall frost is October 11, giving you a growing season of approximately 170 days.

At an elevation of 1,182 feet, Clarke County receives approximately 35.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Feverfew during the growing season.

Clarke County, IA (Zone 5b) Moderate season
170 days
Last Spring Frost April 24
170 growing days
First Fall Frost October 11

Clarke County Soil Profile

Soil Type

Silt Loam

Soil pH

6-6.9

Drainage

Well Drained

Feverfew Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Apr 25 🍅 Harvest: Jul 25 – Oct 10
Recommended (50%) ✗ May not fit
Transplant: May 1 🍅 Harvest: Jul 31 – Oct 16
Safe Start (90%) ✗ May not fit
Transplant: May 16 🍅 Harvest: Aug 15 – Oct 31

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 Clarke County

How your county's soil matches Feverfew's growing requirements.

Soil pH

Your soil pH (6.0–6.9) is within Feverfew's preferred range (6.0–7.0).

Soil Texture

The silt loam soil in Clarke County is excellent for Feverfew — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.4%) — Feverfew will thrive.

How to Plant Feverfew

0.5"
Planting Depth
8"
Between Plants
12"
Between Rows

Feverfew Water Budget

Plant needs
0.5″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

Monthly Watering Guide for Feverfew

Feverfew needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Feverfew Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 1.7" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 2.2" 3.5" 0" ✅ Rainfall sufficient
May 2.2" 4.5" 0" ✅ Rainfall sufficient
Jun 2.2" 4" 0" ✅ Rainfall sufficient
Jul 2.2" 3.7" 0" ✅ Rainfall sufficient
Aug 2.2" 3.9" 0" ✅ Rainfall sufficient
Sep 2.2" 3.2" 0" ✅ Rainfall sufficient
Oct 2.2" 3.1" 0" ✅ Rainfall sufficient
Nov 2.3" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

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

Feverfew 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.

Feverfew needs ~1,601 GDD — county provides 2,592 GDD Excellent fit

Feverfew Planting Timeline — Clarke County, IA

Feverfew Planting Calendar

Activity When Date Range
Transplant Outdoors May 1 May 1 – May 15
Harvest July 31 Jul 31 – Oct 16

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 Harvest
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

90–120 days

🧪 Soil pH

Needs 6–7 · Your soil: ideal

🗺️ USDA Zone

Zone 5b

📆 Growing Season

170 days in Clarke County

Growing Tips for Feverfew in Clarke County

Direct sow Feverfew outdoors after April 24 in Clarke County when soil has warmed and frost danger has passed.

Common pests for Feverfew in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors or direct sow on the soil surface. Deadhead regularly to prevent aggressive self-seeding. Divide clumps every 2-3 years to maintain vigor.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Feverfew in Clarke County, IA?

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

What planting zone is Clarke County, IA?

Clarke County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 24 and first fall frost is October 11.

When should I plant Feverfew in Clarke County, IA?

In Clarke County, IA, plant Feverfew after the last frost (around April 24) and before the first frost (around October 11). Best results when soil holds above 50°F.

What growing zone is Clarke County, IA for Feverfew?

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

Can Feverfew grow in Clarke County's climate?

Yes — Feverfew grows well in Clarke County's temperate climate. Clarke County averages a 170-day frost-free season, with last frost around April 24 and first frost around October 11.

🌱

Your Clarke County Garden Planner — Free

A 22-page printable planner built for Clarke 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.

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

Sources & credits

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