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

Mesa County County's spring Bachelor's Button window runs March 27 through April 17. most warm-season crops establish quickly once soil holds above 60°F. A second sowing from August 14 to August 28 extends the harvest into fall.

When to Plant Bachelor's Button in Mesa County, CO

Mesa County, Colorado Zone 7a June

Top priorities for Mesa County, Colorado gardeners in June

If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.

Avg. last frost May 1
Avg. first frost October 9
Soil temp (4") 58°F
Watering High
Pest pressure High
Daylight 14.7 hrs
  1. Fire up the seed-starting tray: bachelor's button

    Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.

July prep starts now
  • 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.

Mesa County, Colorado is in USDA Zone 7a. The average last spring frost is May 1 and the first fall frost is October 9, giving you a growing season of approximately 161 days.

At an elevation of 6,091 feet, Mesa County receives approximately 23.3 inches of rainfall annually with predominantly loam soil. Summer highs average 91°F, providing good warmth for Bachelor's Button during the growing season.

Annual Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Mesa County, CO (Zone 7a) Moderate season
161 days
Last Spring Frost May 1
161 growing days
First Fall Frost October 9
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Mesa County Soil Profile

Soil Type

Loam

Soil pH

6.7-8.1

Drainage

Well Drained

Bachelor's Button Planting Risk Windows

Early Start (70% safe) ✓ Fits season (11 days to spare)
Start indoors: Mar 11 Transplant: Apr 22 🌸 Bloom: Jun 24 – Sep 23
Recommended (50%) ✓ Fits season (7 days to spare)
Start indoors: Mar 20 Transplant: May 1 🌸 Bloom: Jul 3 – Oct 2
Safe Start (90%) ✓ Fits season (10 days to spare)
Start indoors: Apr 2 Transplant: May 14 🌸 Bloom: Jul 16 – Oct 15

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 Mesa County

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

Soil pH

Your soil pH (6.7–8.1) overlaps with Bachelor's Button's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.7%). Annual compost additions will help Bachelor's Button.

How to Plant Bachelor's Button

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

Fall planting: Sow 8 weeks before your first frost date for a fall harvest.

Succession Planting Bachelor's Button

3
successive plantings in your 161-day season

Sow every 6.9 weeks. Last sowing by Jul 11 to harvest before frost.

For a dedicated fall crop, sow by Aug 14.

Bachelor's Button Water Budget

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

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 1.7" 0" ❄️ Dormant
Feb 1.2" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 2.5" 0" ❄️ Dormant
May 2.2" 2.6" 0" ✅ Rainfall sufficient
Jun 2.2" 1.8" 0.4" 💧 Light watering
Jul 2.2" 2.1" 0.1" 💧 Light watering
Aug 2.2" 2.5" 0" ✅ Rainfall sufficient
Sep 2.2" 1.9" 0.3" 💧 Light watering
Oct 2.2" 1.8" 0.4" 💧 Light watering
Nov 1.7" 0" ❄️ Dormant
Dec 1.2" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Mesa 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 ~1,369 GDD — county provides 2,938 GDD Excellent fit

Bachelor's Button Planting Timeline — Mesa County, CO

Bachelor's Button Planting Calendar

Activity When Date Range
Start Indoors March 20 Mar 20 – Apr 3
Transplant Outdoors May 1 May 1 – May 15
Direct Sow March 27 Mar 27 – Apr 17
Bloom July 3 Jul 3 – Oct 2
Fall Sowing August 14 Aug 14 – Aug 28

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

Month-by-Month Timeline

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

🗺️ USDA Zone

Zone 7a

📆 Growing Season

161 days in Mesa County

Growing Tips for Bachelor's Button in Mesa County

Direct sow Bachelor's Button outdoors after May 01 in Mesa 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.

Mesa County receives only 23" of rain annually. Bachelor's Button needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

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 Mesa County, CO?

Mesa County is in Zone 7a with an average last frost of May 1. Plan your Bachelor's Button planting based on this frost date — see the calendar above for exact timing.

What planting zone is Mesa County, CO?

Mesa County, Colorado is in USDA Hardiness Zone 7a. The average last spring frost is May 1 and first fall frost is October 9.

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

In Mesa County, , plant Bachelor's Button after the last frost (around May 1) and before the first frost (around October 9). Best results when soil holds above 50°F.

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

Mesa County sits in USDA Zone 7a. Bachelor's Button grows reliably in zones 2a through 11b, so it's a good fit here.

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

Yes — Bachelor's Button grows well in Mesa County's temperate climate. Mesa County averages a 161-day frost-free season, with last frost around May 1 and first frost around October 9.

🌱

Your Mesa County Garden Planner — Free

A 22-page printable planner built for Mesa County (Zone 7a). 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 Mesa County, CO. 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.