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When to Plant Feverfew in Webster County, IA

Webster County, Iowa Zone 5a May

Your May game plan for Webster County, Iowa

If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.

Avg. last frost April 28
Avg. first frost October 6
Soil temp (4") 54°F
Watering Moderate
Pest pressure Low
Daylight 14.4 hrs
  1. Get feverfew in the ground

    Frost risk is low now in Webster County, Iowa. If you've been covering beds overnight, you can stop.

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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.

Webster County, Iowa is in USDA Zone 5a. The average last spring frost is April 28 and the first fall frost is October 6, giving you a growing season of approximately 161 days.

At an elevation of 1,065 feet, Webster County receives approximately 30.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Feverfew to ensure they mature before fall.

Webster County, IA (Zone 5a) Moderate season
161 days
Last Spring Frost April 28
161 growing days
First Fall Frost October 6
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Webster County Soil Profile

Soil Type

Silt Loam

Soil pH

6.2-7.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: Apr 29 🍅 Harvest: Jul 29 – Oct 14
Recommended (50%) ✗ May not fit
Transplant: May 5 🍅 Harvest: Aug 4 – Oct 20
Safe Start (90%) ✗ May not fit
Transplant: May 21 🍅 Harvest: Aug 20 – Nov 5

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 Webster County

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

Soil pH

Your soil pH (6.2–7.3) overlaps with Feverfew's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Feverfew.

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

Plant Water Budget

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

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 1.4" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 2.3" 0" ❄️ Dormant
Apr 2.2" 2.6" 0" ✅ Rainfall sufficient
May 2.2" 3.4" 0" ✅ Rainfall sufficient
Jun 2.2" 3.6" 0" ✅ Rainfall sufficient
Jul 2.2" 3.1" 0" ✅ Rainfall sufficient
Aug 2.2" 3" 0" ✅ Rainfall sufficient
Sep 2.2" 3.2" 0" ✅ Rainfall sufficient
Oct 2.2" 2.5" 0" ✅ Rainfall sufficient
Nov 2.2" 0" ❄️ Dormant
Dec 1.7" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Webster 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 ~1,050 GDD — county provides 1,610 GDD Excellent fit

Feverfew Planting Timeline — Webster County, IA

Feverfew Planting Calendar

Activity When Date Range
Transplant Outdoors May 5 May 5 – May 19
Harvest August 4 Aug 4 – Oct 20

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

Month-by-Month Timeline

MonthActivities
January
February
March
April
May Transplant Outdoors
June
July
August Harvest
September Harvest
October Harvest
November
December
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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: acceptable

🗺️ USDA Zone

Zone 5a

📆 Growing Season

161 days in Webster County

Growing Tips for Feverfew in Webster County

Direct sow Feverfew outdoors after April 28 in Webster 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 Webster County, IA?

Webster County is in Zone 5a with an average last frost of April 28. Plan your Feverfew planting based on this frost date — see the calendar above for exact timing.

What planting zone is Webster County, IA?

Webster County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 28 and first fall frost is October 6.

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Your Webster County Garden Planner — Free

A 24-page printable planner built for Webster County (Zone 5a). 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 Webster County, IA. Local conditions may vary. Last updated: May 2026.

Sources & credits

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