Blog

When to plant Bachelor's Button in Davis County, IA

Plant Bachelor's Button in Davis County from March 29 to April 19 in spring. Davis County sits in USDA Zone 5b, with last frost around April 19 and first frost on October 16.

When to Plant Bachelor's Button in Davis County, IA

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.

Davis County, Iowa is in USDA Zone 5b. The average last spring frost is April 19 and the first fall frost is October 16, giving you a growing season of approximately 180 days.

At an elevation of 859 feet, Davis County receives approximately 30.3 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
Davis County, IA (Zone 5b) Moderate season
180 days
Last Spring Frost April 19
180 growing days
First Fall Frost October 16

Davis County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Bachelor's Button Planting Timeline — Davis County, IA

Bachelor's Button Planting Calendar

Activity When Date Range
Start Indoors March 8 Mar 8 – Mar 22
Transplant Outdoors April 19 Apr 19 – May 3
Direct Sow March 29 Mar 29 – Apr 19
Bloom June 21 Jun 21 – Sep 6

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 Transplant Outdoors
June Bloom
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 5b

📆 Growing Season

180 days in Davis County

Growing Tips for Davis 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 Davis County, IA?

Davis County is in Zone 5b with an average last frost of April 19. Plan your Bachelor's Button planting based on this frost date — see the calendar above for exact timing.

What planting zone is Davis County, IA?

Davis County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 19 and first fall frost is October 16.

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

In Davis County, IA, plant Bachelor's Button after the last frost (around April 19) and before the first frost (around October 16). Best results when soil holds above 50°F.

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

Davis 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 Davis County's climate?

Yes — Bachelor's Button grows well in Davis County's temperate climate. Davis County averages a 180-day frost-free season, with last frost around April 19 and first frost around October 16.

🌱

Your Davis County Garden Planner — Free

A 22-page printable planner built for Davis 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 Davis County, IA. Local conditions may vary. Last updated: July 2026.

Sources & credits

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