When to plant Bachelor's Button in Jerome County, ID
Plant Bachelor's Button in Jerome County, when soil hits 50°F — usually April 12. Continue planting through May 3 for the spring crop. A second sowing from August 23 to September 6 extends the harvest into fall.
When to Plant Bachelor's Button in Jerome County, ID
Your June planting checklist for Jerome County, Idaho
A quick June briefing for Jerome County, Idaho gardeners — what's urgent, what's next, and what can wait.
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.
Jerome County, Idaho is in USDA Zone 6b. The average last spring frost is May 10 and the first fall frost is October 4, giving you a growing season of approximately 147 days.
At an elevation of 6,306 feet, Jerome County receives approximately 13.5 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Bachelor's Button during the growing season. With low rainfall, drip irrigation is essential for growing Bachelor's Button successfully. Mulch heavily to conserve soil moisture.
Jerome County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.9
Drainage
Well Drained
Bachelor's Button Planting Risk Windows
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 Jerome County
How your county's soil matches Bachelor's Button's growing requirements.
Soil pH
Your soil pH (6.8–7.9) overlaps with Bachelor's Button's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Jerome County is excellent for Bachelor's Button — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.8%). Annual compost additions will help Bachelor's Button.
How to Plant Bachelor's Button
Fall planting: Sow 6 weeks before your first frost date for a fall harvest.
Succession Planting Bachelor's Button
Sow every 6.9 weeks. Last sowing by Jul 06 to harvest before frost.
For a dedicated fall crop, sow by Aug 23.
Bachelor's Button Water Budget
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" | 0" | ❄️ Dormant |
| Feb | — | 0.8" | 0" | ❄️ Dormant |
| Mar | — | 1.3" | 0" | ❄️ Dormant |
| Apr | — | 1.6" | 0" | ❄️ Dormant |
| May | 2.2" | 1.5" | 0.7" | 💧 Light watering |
| Jun | 2.2" | 1" | 1.2" | 🚿 Regular watering |
| Jul | 2.2" | 1.2" | 1" | 💧 Light watering |
| Aug | 2.2" | 1.3" | 0.9" | 💧 Light watering |
| Sep | 2.2" | 1.1" | 1.1" | 🚿 Regular watering |
| Oct | 2.2" | 1.1" | 1.1" | 🚿 Regular watering |
| Nov | — | 0.8" | 0" | ❄️ Dormant |
| Dec | — | 0.8" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Jerome 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 Planting Timeline — Jerome County, ID
Bachelor's Button Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 29 | Mar 29 – Apr 12 |
| Transplant Outdoors | May 10 | May 10 – May 24 |
| Direct Sow | April 12 | Apr 12 – May 3 |
| Bloom | July 12 | Jul 12 – Oct 4 |
| Fall Sowing | August 23 | Aug 23 – Sep 6 |
Plant 0.3" deep · 12" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Bloom |
| August | Fall Sowing Bloom |
| September | Fall Sowing Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Only during dry spells
📅 Days to Maturity
60–90 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
147 days in Jerome County
Growing Tips for Bachelor's Button in Jerome County
Direct sow Bachelor's Button outdoors after May 10 in Jerome 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.
Jerome County receives only 14" 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 →
Bachelor's Button in Other Locations
Frequently Asked Questions
When should I plant Bachelor's Button in Jerome County, ID?
Jerome County is in Zone 6b with an average last frost of May 10. Plan your Bachelor's Button planting based on this frost date — see the calendar above for exact timing.
What planting zone is Jerome County, ID?
Jerome County, Idaho is in USDA Hardiness Zone 6b. The average last spring frost is May 10 and first fall frost is October 4.
When should I plant Bachelor's Button in Jerome County, ID?
In Jerome County, ID, plant Bachelor's Button after the last frost (around May 10) and before the first frost (around October 4). Best results when soil holds above 50°F.
What growing zone is Jerome County, ID for Bachelor's Button?
Jerome County sits in USDA Zone 6b. Bachelor's Button grows reliably in zones 2a through 11b, so it's a good fit here.
Can Bachelor's Button grow in Jerome County's climate?
Yes — Bachelor's Button grows well in Jerome County's temperate climate. Jerome County averages a 147-day frost-free season, with last frost around May 10 and first frost around October 4.
Your Jerome County Garden Planner — Free
A 22-page printable planner built for Jerome County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.