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When to plant Bachelor's Button in Stearns County, MN

The best window to plant Bachelor's Button in Stearns County, is April 19–May 10, when soil warms to 50°F. Last frost typically hits May 3; first frost October 6.

When to Plant Bachelor's Button in Stearns County, MN

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.

Stearns County, Minnesota is in USDA Zone 4b. The average last spring frost is May 3 and the first fall frost is October 6, giving you a growing season of approximately 156 days.

At an elevation of 772 feet, Stearns County receives approximately 37.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Bachelor's Button to ensure they mature before fall.

Annual Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Stearns County, MN (Zone 4b) Moderate season
156 days
Last Spring Frost May 3
156 growing days
First Fall Frost October 6

Stearns County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Bachelor's Button Planting Timeline — Stearns County, MN

Bachelor's Button Planting Calendar

Activity When Date Range
Start Indoors March 15 Mar 15 – Mar 29
Transplant Outdoors May 3 May 3 – May 17
Direct Sow April 19 Apr 19 – May 10
Bloom July 5 Jul 5 – Sep 6

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Direct Sow
May Transplant Outdoors Direct Sow
June
July Bloom
August Bloom
September 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 4b

📆 Growing Season

156 days in Stearns County

Growing Tips for Stearns 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 Stearns County, MN?

Stearns County is in Zone 4b with an average last frost of May 3. Plan your Bachelor's Button planting based on this frost date — see the calendar above for exact timing.

What planting zone is Stearns County, MN?

Stearns County, Minnesota is in USDA Hardiness Zone 4b. The average last spring frost is May 3 and first fall frost is October 6.

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

In Stearns County, MN, plant Bachelor's Button after the last frost (around May 3) and before the first frost (around October 6). Best results when soil holds above 50°F.

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

Stearns County sits in USDA Zone 4b. Bachelor's Button grows reliably in zones 2a through 11b, so it's a good fit here.

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

Yes — Bachelor's Button grows well in Stearns County's temperate climate. Stearns County averages a 156-day frost-free season, with last frost around May 3 and first frost around October 6.

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Your Stearns County Garden Planner — Free

A 22-page printable planner built for Stearns County (Zone 4b). 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 Stearns County, MN. Local conditions may vary. Last updated: June 2026.

Sources & credits

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