Blog

When to Plant Bachelor's Button in Hood River County, OR

Hood River County, Oregon Zone 7b June

Hood River County, Oregon gardeners: here's your June plan

Each item below is timed to Hood River County, Oregon's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost April 14
Avg. first frost October 19
Soil temp (4") 78°F
Watering High
Pest pressure High
Daylight 15.5 hrs

Instant PDF download. No spam, unsubscribe any time.

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.

Hood River County, Oregon is in USDA Zone 7b. The average last spring frost is April 14 and the first fall frost is October 19, giving you a growing season of approximately 188 days.

At an elevation of 127 feet, Hood River County receives approximately 50.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Bachelor's Button during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Bachelor's Button root diseases.

Annual Blooms in Spring Pollinator-friendly Deer-resistant Good for cutting
Hood River County, OR (Zone 7b) Moderate season
188 days
Last Spring Frost April 14
188 growing days
First Fall Frost October 19

Hood River County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.5

Drainage

Well Drained

Bachelor's Button Planting Risk Windows

Early Start (70% safe) ✓ Fits season (25 days to spare)
Start indoors: Feb 25 Transplant: Apr 8 🌸 Bloom: Jun 10 – Sep 16
Recommended (50%) ✓ Fits season (27 days to spare)
Start indoors: Mar 3 Transplant: Apr 14 🌸 Bloom: Jun 16 – Sep 22
Safe Start (90%) ✓ Fits season (28 days to spare)
Start indoors: Mar 25 Transplant: May 6 🌸 Bloom: Jul 8 – 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 Hood River County

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

Soil pH

Your soil pH (5.7–6.5) overlaps with Bachelor's Button's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.7%) — Bachelor's Button will thrive.

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 188-day season

Sow every 6.9 weeks. Last sowing by Jul 21 to harvest before frost.

For a dedicated fall crop, sow by Aug 24.

Bachelor's Button Water Budget

Plant needs
0.5″/week
Rainfall provides
1.1″/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 8.1" 0" ❄️ Dormant
Feb 5.4" 0" ❄️ Dormant
Mar 5.2" 0" ❄️ Dormant
Apr 2.2" 4.1" 0" ✅ Rainfall sufficient
May 2.2" 2.7" 0" ✅ Rainfall sufficient
Jun 2.2" 2.1" 0.1" 💧 Light watering
Jul 2.2" 0.9" 1.3" 🚿 Regular watering
Aug 2.2" 0.8" 1.4" 🚿 Regular watering
Sep 2.2" 2.2" 0" ✅ Rainfall sufficient
Oct 2.2" 4.3" 0" ✅ Rainfall sufficient
Nov 7.7" 0" ❄️ Dormant
Dec 7.4" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Hood River 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 ~1,144 GDD — county provides 2,867 GDD Excellent fit

Bachelor's Button Planting Timeline — Hood River County, OR

Bachelor's Button Planting Calendar

Activity When Date Range
Start Indoors March 3 Mar 3 – Mar 17
Transplant Outdoors April 14 Apr 14 – Apr 28
Direct Sow March 10 Mar 10 – Mar 31
Bloom June 16 Jun 16 – Sep 22
Fall Sowing August 24 Aug 24 – Sep 7

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

Month-by-Month Timeline

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

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 7b

📆 Growing Season

188 days in Hood River County

Growing Tips for Bachelor's Button in Hood River County

Direct sow Bachelor's Button outdoors after April 14 in Hood River 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 Hood River County, OR?

Hood River County is in Zone 7b with an average last frost of April 14. Plan your Bachelor's Button planting based on this frost date — see the calendar above for exact timing.

What planting zone is Hood River County, OR?

Hood River County, Oregon is in USDA Hardiness Zone 7b. The average last spring frost is April 14 and first fall frost is October 19.

🌱

Your Hood River County Garden Planner — Free

A 22-page printable planner built for Hood River County (Zone 7b). 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 Hood River County, OR. 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.