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

In Kennebec County County, Bachelor's Button is a single-season spring crop — there's no second fall window. Plant April 19–May 10 for an 90-day harvest, finishing well before the October 5 first frost.

When to Plant Bachelor's Button in Kennebec County, ME

Kennebec County, Maine Zone 5b June

June to-do list for Kennebec County, Maine

June is a pivotal month for Kennebec County, Maine gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost May 10
Avg. first frost October 5
Soil temp (4") 68°F
Watering Moderate
Pest pressure High
Daylight 15.3 hrs
  1. Start bachelor's button under lights

    Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.

July will be here before you know it — start on
  • First harvests: bachelor's button

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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.

Kennebec County, Maine is in USDA Zone 5b. The average last spring frost is May 10 and the first fall frost is October 5, giving you a growing season of approximately 148 days.

At an elevation of 1,032 feet, Kennebec County receives approximately 42.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°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
Kennebec County, ME (Zone 5b) Short season
148 days
Last Spring Frost May 10
148 growing days
First Fall Frost October 5
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Kennebec County Soil Profile

Soil Type

Silt Loam

Soil pH

5.1-6.4

Drainage

Well Drained

Bachelor's Button Planting Risk Windows

Early Start (70% safe) ✓ Fits season (5 days to spare)
Start indoors: Mar 23 Transplant: May 4 🌸 Bloom: Jul 6 – Sep 21
Recommended (50%) ✓ Fits season (8 days to spare)
Start indoors: Mar 29 Transplant: May 10 🌸 Bloom: Jul 12 – Sep 27
Safe Start (90%) ✓ Fits season (5 days to spare)
Start indoors: Apr 15 Transplant: May 27 🌸 Bloom: Jul 29 – Oct 14

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 Kennebec County

How your county's soil matches Bachelor's Button's growing requirements.

Soil pH

Your soil pH (5.1–6.4) is more acidic than Bachelor's Button prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Kennebec County is excellent for Bachelor's Button — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.5%). Annual compost additions will help Bachelor's Button.

How to Plant Bachelor's Button

0.3"
Planting Depth
12"
Between Plants
12"
Between Rows

Succession Planting Bachelor's Button

2
successive plantings in your 148-day season

Sow every 6.9 weeks. Last sowing by Jul 07 to harvest before frost.

Bachelor's Button Water Budget

Plant needs
0.5″/week
Rainfall provides
1.2″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Bachelor's Button

Bachelor's Button 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 Bachelor's Button Needs Rainfall You Supplement Action
Jan 3.3" 0" ❄️ Dormant
Feb 2.8" 0" ❄️ Dormant
Mar 3.5" 0" ❄️ Dormant
Apr 3.4" 0" ❄️ Dormant
May 2.2" 3.7" 0" ✅ Rainfall sufficient
Jun 2.2" 3.7" 0" ✅ Rainfall sufficient
Jul 2.2" 3.9" 0" ✅ Rainfall sufficient
Aug 2.2" 4" 0" ✅ Rainfall sufficient
Sep 2.2" 3.9" 0" ✅ Rainfall sufficient
Oct 2.2" 3.8" 0" ✅ Rainfall sufficient
Nov 3.1" 0" ❄️ Dormant
Dec 3.4" 0" ❄️ Dormant

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

Bachelor's Button 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.

Bachelor's Button needs ~975 GDD — county provides 1,924 GDD Excellent fit

Bachelor's Button Planting Timeline — Kennebec County, ME

Bachelor's Button Planting Calendar

Activity When Date Range
Start Indoors March 29 Mar 29 – Apr 12
Transplant Outdoors May 10 May 10 – May 24
Direct Sow April 19 Apr 19 – May 10
Bloom July 12 Jul 12 – Sep 27

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 5b

📆 Growing Season

148 days in Kennebec County

Growing Tips for Bachelor's Button in Kennebec County

Direct sow Bachelor's Button outdoors after May 10 in Kennebec County when soil has warmed and frost danger has passed.

Common pests for Bachelor's Button in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

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 Kennebec County, ME?

Kennebec County is in Zone 5b with an average last frost of May 10. Plan your Bachelor's Button planting based on this frost date — see the calendar above for exact timing.

What planting zone is Kennebec County, ME?

Kennebec County, Maine is in USDA Hardiness Zone 5b. The average last spring frost is May 10 and first fall frost is October 5.

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

In Kennebec County County, , plant Bachelor's Button after the last frost (around May 10) and before the first frost (around October 5). Best results when soil holds above 50°F.

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

Kennebec 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 Kennebec County County's climate?

Yes — Bachelor's Button grows well in Kennebec County County's temperate climate. Kennebec County County averages a 148-day frost-free season, with last frost around May 10 and first frost around October 5.

🌱

Your Kennebec County Garden Planner — Free

A 22-page printable planner built for Kennebec 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.

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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 Kennebec County, ME. 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.