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When to plant Feverfew in Bartlett, IL

Bartlett's 177-day season only supports one Feverfew planting per year. Sow between April 30 and May 14 for the best chance at full maturity before October 17.

When to Plant Feverfew in Bartlett, IL

Cook County, Illinois Zone 6a August

Top priorities for Cook County, Illinois gardeners in August

Your garden in Cook County, Illinois is working on a schedule, even when you're not. Here's where you should be this August.

Avg. last frost April 23
Avg. first frost October 17
Soil temp (4") 76°F
Watering Moderate
Pest pressure High
Daylight 13.7 hrs
  1. It's harvest week for feverfew

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

September will be here before you know it — start on
  • 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.

Bartlett, Illinois is in USDA Zone 6a. The average last spring frost is April 23 and the first fall frost is October 17, giving you a growing season of approximately 177 days.

At an elevation of 728 feet, Cook County receives approximately 35.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Feverfew during the growing season.

Bartlett, IL (Zone 6a) Moderate season
177 days
Last Spring Frost April 23
177 growing days
First Fall Frost October 17

Bartlett Soil Profile

Soil Type

Silt Loam

Soil pH

6-7

Drainage

Well Drained

Feverfew Planting Risk Windows

Early Start (70% safe) ✓ Fits season (1 days to spare)
Transplant: Apr 25 🍅 Harvest: Jul 25 – Oct 10
Recommended (50%) ✓ Fits season (2 days to spare)
Transplant: Apr 30 🍅 Harvest: Jul 30 – Oct 15
Safe Start (90%) ✗ May not fit
Transplant: May 17 🍅 Harvest: Aug 16 – Nov 1

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 Bartlett

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

Soil pH

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

Soil Texture

The silt loam soil in Cook 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
0.8″/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 1.5" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 2.2" 3.6" 0" ✅ Rainfall sufficient
May 2.2" 4.1" 0" ✅ Rainfall sufficient
Jun 2.2" 4.7" 0" ✅ Rainfall sufficient
Jul 2.2" 3.7" 0" ✅ Rainfall sufficient
Aug 2.2" 3.2" 0" ✅ Rainfall sufficient
Sep 2.2" 2.9" 0" ✅ Rainfall sufficient
Oct 2.2" 3" 0" ✅ Rainfall sufficient
Nov 2.3" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Cook 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 ~1,444 GDD — county provides 2,433 GDD Excellent fit

Feverfew Planting Timeline — Bartlett, IL

Feverfew Planting Calendar

Activity When Date Range
Transplant Outdoors April 30 Apr 30 – May 14
Harvest July 30 Jul 30 – Oct 15

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

Month-by-Month Timeline

MonthActivities
January
February
March
April Transplant Outdoors
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 6a

📆 Growing Season

177 days in Cook County

Growing Tips for Feverfew in Bartlett

Direct sow Feverfew outdoors after April 23 in Cook 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 →

When should I plant Feverfew in Bartlett, IL?

In Bartlett, IL, plant Feverfew after the last frost (around April 23) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is Bartlett, IL for Feverfew?

Bartlett sits in USDA Zone 6a. Feverfew grows reliably in zones 5a through 9b, so it's a good fit here.

Can Feverfew grow in Bartlett's climate?

Yes — Feverfew grows well in Bartlett's temperate climate. Bartlett averages a 177-day frost-free season, with last frost around April 23 and first frost around October 17.

🌱

Your Cook County Garden Planner — Free

A 22-page printable planner built for Cook County (Zone 6a). 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 Cook County, IL. Local conditions may vary. Last updated: August 2026.