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When to plant Bachelor's Button in Ogle County County,

The best window to plant Bachelor's Button in Ogle County County, is April 2–April 23, when soil warms to 50°F. Last frost typically hits April 23; first frost October 13.

When to Plant Bachelor's Button in Ogle 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.

Ogle County, Illinois is in USDA Zone 5b. The average last spring frost is April 23 and the first fall frost is October 13, giving you a growing season of approximately 173 days.

At an elevation of 890 feet, Ogle County receives approximately 39.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Bachelor's Button during the growing season.

Annual Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Ogle County, IL (Zone 5b) Moderate season
173 days
Last Spring Frost April 23
173 growing days
First Fall Frost October 13
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Ogle County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.9

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 1.5" 0" ❄️ Dormant
Feb 1.9" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 4.3" 3.9" 0.4" 💧 Light watering
May 4.3" 4.1" 0.2" 💧 Light watering
Jun 4.3" 5" 0" ✅ Rainfall sufficient
Jul 4.3" 5" 0" ✅ Rainfall sufficient
Aug 4.3" 4" 0.3" 💧 Light watering
Sep 4.3" 3.9" 0.4" 💧 Light watering
Oct 4.3" 3.1" 1.2" 💧 Light watering
Nov 2.5" 0" ❄️ Dormant
Dec 2.3" 0" ❄️ Dormant

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

Bachelor's Button Planting Timeline — Ogle County, IL

Bachelor's Button Planting Calendar

Activity When Date Range
Start Indoors March 12 Mar 12 – Mar 26
Transplant Outdoors April 23 Apr 23 – May 7
Direct Sow April 2 Apr 2 – Apr 23
Bloom June 25 Jun 25 – Sep 10

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Transplant Outdoors Direct Sow
May Transplant Outdoors
June Bloom
July Bloom
August Bloom
September Bloom
October
November
December
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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 5b

📆 Growing Season

173 days in Ogle County

Growing Tips for Ogle 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 Ogle County, IL?

Ogle County is in Zone 5b with an average last frost of April 23. Plan your Bachelor's Button planting based on this frost date — see the calendar above for exact timing.

What planting zone is Ogle County, IL?

Ogle County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 23 and first fall frost is October 13.

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

In Ogle County County, , plant Bachelor's Button after the last frost (around April 23) and before the first frost (around October 13). Best results when soil holds above 50°F.

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

Ogle County County sits in USDA Zone 5b. Bachelor's Button grows reliably in zones 2a through 11b, so it's a good fit here.

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

Yes — Bachelor's Button grows well in Ogle County County's temperate climate. Ogle County County averages a 173-day frost-free season, with last frost around April 23 and first frost around October 13.

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Your Ogle County Garden Planner — Free

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

Sources & credits

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