When to plant Bachelor's Button in Bingham County, ID
In Bingham County, Bachelor's Button is a spring-only crop. Plant April 30–May 21 once soil hits 50°F.
When to Plant Bachelor's Button in Bingham County, ID
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.
Bingham County, Idaho is in USDA Zone 5b. The average last spring frost is May 21 and the first fall frost is September 21, giving you a growing season of approximately 123 days.
At an elevation of 8,345 feet, Bingham County receives approximately 24.5 inches of rainfall annually with predominantly loam soil. Summer highs average 86°F, providing good warmth for Bachelor's Button during the growing season.
Bingham County Soil Profile
Soil Type
Loam
Soil pH
6.3-7.7
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 | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.4" | 0" | ❄️ Dormant |
| Mar | — | 2.1" | 0" | ❄️ Dormant |
| Apr | — | 2.9" | 0" | ❄️ Dormant |
| May | 4.3" | 2.5" | 1.8" | 💧 Light watering |
| Jun | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Jul | 4.3" | 2.3" | 2" | 💧 Light watering |
| Aug | 4.3" | 2.5" | 1.8" | 💧 Light watering |
| Sep | 4.3" | 2.3" | 2" | 💧 Light watering |
| Oct | — | 2.4" | 0" | ❄️ Dormant |
| Nov | — | 1.8" | 0" | ❄️ Dormant |
| Dec | — | 1.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Sep in Bingham County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Bachelor's Button Planting Timeline — Bingham County, ID
Bachelor's Button Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 9 | Apr 9 – Apr 23 |
| Transplant Outdoors | May 21 | May 21 – Jun 4 |
| Direct Sow | April 30 | Apr 30 – May 21 |
| Bloom | July 23 | Jul 23 – Oct 8 |
Plant 0.3" deep · 12" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| 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 5b
📆 Growing Season
123 days in Bingham County
Growing Tips for Bingham 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 Bingham County, ID?
Bingham County is in Zone 5b with an average last frost of May 21. Plan your Bachelor's Button planting based on this frost date — see the calendar above for exact timing.
What planting zone is Bingham County, ID?
Bingham County, Idaho is in USDA Hardiness Zone 5b. The average last spring frost is May 21 and first fall frost is September 21.
When should I plant Bachelor's Button in Bingham County, ID?
In Bingham County, ID, plant Bachelor's Button after the last frost (around May 21) and before the first frost (around September 21). Best results when soil holds above 50°F.
What growing zone is Bingham County, ID for Bachelor's Button?
Bingham 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 Bingham County's climate?
Yes — Bachelor's Button grows well in Bingham County's temperate climate. Bingham County averages a 123-day frost-free season, with last frost around May 21 and first frost around September 21.
Your Bingham County Garden Planner — Free
A 22-page printable planner built for Bingham 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.