When to Plant Bachelor's Button in Wasco County, OR
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.
Wasco County, Oregon is in USDA Zone 7a. The average last spring frost is April 23 and the first fall frost is October 12, giving you a growing season of approximately 172 days.
At an elevation of 432 feet, Wasco County receives approximately 35.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Bachelor's Button to ensure they mature before fall.
Wasco County Soil Profile
Soil Type
Silt Loam
Soil pH
5.2-6.3
Drainage
Well Drained
Monthly Watering Guide for Bachelor's Button
Bachelor's Button needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Bachelor's Button Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 4.3" | 0" | ❄️ Dormant |
| Feb | — | 4" | 0" | ❄️ Dormant |
| Mar | — | 4" | 0" | ❄️ Dormant |
| Apr | 4.3" | 2.6" | 1.7" | 💧 Light watering |
| May | 4.3" | 2.1" | 2.2" | 🚿 Regular watering |
| Jun | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Jul | 4.3" | 0.6" | 3.7" | 🚿 Regular watering |
| Aug | 4.3" | 0.7" | 3.6" | 🚿 Regular watering |
| Sep | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Oct | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Nov | — | 5.1" | 0" | ❄️ Dormant |
| Dec | — | 5.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Wasco County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Bachelor's Button Planting Timeline — Wasco County, OR
Bachelor's Button Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 12 | Mar 12 – Mar 26 |
| Transplant Outdoors | April 23 | Apr 23 – May 7 |
| Direct Sow | March 19 | Mar 19 – Apr 9 |
| Bloom | June 25 | Jun 25 – Sep 24 |
| Fall Sowing | August 17 | Aug 17 – Aug 31 |
Plant 0.3" deep · 12" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | Bloom |
| July | Bloom |
| August | Fall Sowing 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 7a
📆 Growing Season
172 days in Wasco County
Growing Tips for Wasco 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 →
Bachelor's Button in Other Locations
Frequently Asked Questions
When should I plant Bachelor's Button in Wasco County, OR?
Wasco County is in Zone 7a with an average last frost of April 23. Plan your Bachelor's Button planting based on this frost date — see the calendar above for exact timing.
What planting zone is Wasco County, OR?
Wasco County, Oregon is in USDA Hardiness Zone 7a. The average last spring frost is April 23 and first fall frost is October 12.
Your Wasco County Garden Planner — Free
A 22-page printable planner built for Wasco 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.