When to Plant Bachelor's Button in King County, TX
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.
King County, Texas is in USDA Zone 8a. The average last spring frost is March 31 and the first fall frost is November 7, giving you a growing season of approximately 221 days.
At an elevation of 3,170 feet, King County receives approximately 60.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 99°F, so Bachelor's Button may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Bachelor's Button will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Bachelor's Button root diseases.
King County Soil Profile
Soil Type
Sandy Loam
Soil pH
7.8-8.4
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 | — | 4.7" | 0" | ❄️ Dormant |
| Feb | — | 3.2" | 0" | ❄️ Dormant |
| Mar | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Apr | 4.3" | 2.3" | 2" | 💧 Light watering |
| May | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Jun | 4.3" | 2.2" | 2.1" | 💧 Light watering |
| Jul | 4.3" | 10.4" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 11.5" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 8.1" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 5.7" | 0" | ✅ Rainfall sufficient |
| Nov | 4.3" | 3" | 1.3" | 💧 Light watering |
| Dec | — | 3.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in King County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Bachelor's Button Planting Timeline — King County, TX
Bachelor's Button Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Transplant Outdoors | March 17 | Mar 17 – Mar 31 |
| Direct Sow | February 17 | Feb 17 – Mar 10 |
| Bloom | May 19 | May 19 – Sep 1 |
| Fall Sowing | September 12 | Sep 12 – Sep 26 |
Plant 0.3" deep · 12" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | — |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Fall Sowing 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 8a
📆 Growing Season
221 days in King County
Growing Tips for King 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 King County, TX?
King County is in Zone 8a with an average last frost of March 31. Plan your Bachelor's Button planting based on this frost date — see the calendar above for exact timing.
What planting zone is King County, TX?
King County, Texas is in USDA Hardiness Zone 8a. The average last spring frost is March 31 and first fall frost is November 7.
Your King County Garden Planner — Free
A 22-page printable planner built for King County (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.