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When to plant Bachelor's Button in Champaign County, IL

For Champaign County, gardeners: plant Bachelor's Button March 17 through April 7 once soil reads 50°F. A second sowing from September 7 to September 21 extends the harvest into fall.

When to Plant Bachelor's Button in Champaign County, IL

Bachelor's Button (Centaurea cyanus), also called cornflower, is a carefree cool-season annual best known for its vivid cobalt-blue flowers — one of the truest blues in the annual garden. It tolerates light frosts, self-seeds prolifically, and thrives in poor to average soils. A traditional cut flower and pollinator magnet, it has been cultivated in gardens for centuries.

Champaign County, Illinois is in USDA Zone 6a. The average last spring frost is April 14 and the first fall frost is October 19, giving you a growing season of approximately 188 days.

At an elevation of 1,215 feet, Champaign County receives approximately 38.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Bachelor's Button during the growing season.

Annual Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Champaign County, IL (Zone 6a) Moderate season
188 days
Last Spring Frost April 14
188 growing days
First Fall Frost October 19

Champaign County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.8

Drainage

Well Drained

Monthly Watering Guide for Bachelor's Button

Bachelor's Button needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Bachelor's Button Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 1.8" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 4.3" 3.6" 0.7" 💧 Light watering
May 4.3" 4.6" 0" ✅ Rainfall sufficient
Jun 4.3" 4.5" 0" ✅ Rainfall sufficient
Jul 4.3" 4.4" 0" ✅ Rainfall sufficient
Aug 4.3" 3.9" 0.4" 💧 Light watering
Sep 4.3" 4" 0.3" 💧 Light watering
Oct 4.3" 3.1" 1.2" 💧 Light watering
Nov 2.7" 0" ❄️ Dormant
Dec 2.4" 0" ❄️ Dormant

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

Bachelor's Button Planting Timeline — Champaign County, IL

Bachelor's Button Planting Calendar

Activity When Date Range
Start Indoors March 3 Mar 3 – Mar 17
Transplant Outdoors April 14 Apr 14 – Apr 28
Direct Sow March 17 Mar 17 – Apr 7
Bloom June 16 Jun 16 – Sep 1
Fall Sowing September 7 Sep 7 – Sep 21

Plant 0.3" deep · 12" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors Direct Sow
April Transplant Outdoors Direct Sow
May
June Bloom
July Bloom
August Bloom
September Fall Sowing Bloom
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Low — drought tolerant

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 6a

📆 Growing Season

188 days in Champaign County

Growing Tips for Champaign County

Direct-sow in early spring as soon as soil can be worked; seeds need a brief cold period for best germination (refrigerate for a few days before planting if spring arrives quickly). In zones 6+, fall-sow for the earliest spring bloom. Thin to 12 inches; do not over-fertilize — too much nitrogen produces foliage at the expense of flowers. Deadhead to prolong blooming or allow self-seeding for a naturalized colony.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Bachelor's Button in Champaign County, IL?

Champaign County is in Zone 6a with an average last frost of April 14. Plan your Bachelor's Button planting based on this frost date — see the calendar above for exact timing.

What planting zone is Champaign County, IL?

Champaign County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 14 and first fall frost is October 19.

When should I plant Bachelor's Button in Champaign County, IL?

In Champaign County, IL, plant Bachelor's Button after the last frost (around April 14) and before the first frost (around October 19). Best results when soil holds above 50°F.

What growing zone is Champaign County, IL for Bachelor's Button?

Champaign County sits in USDA Zone 6a. Bachelor's Button grows reliably in zones 2a through 11b, so it's a good fit here.

Can Bachelor's Button grow in Champaign County's climate?

Yes — Bachelor's Button grows well in Champaign County's temperate climate. Champaign County averages a 188-day frost-free season, with last frost around April 14 and first frost around October 19.

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Your Champaign County Garden Planner — Free

A 22-page printable planner built for Champaign 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 Champaign County, IL. Local conditions may vary. Last updated: August 2026.

Sources & credits

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