When to plant Bachelor's Button in Putnam County, MO
Putnam County's climate puts the Bachelor's Button spring window between March 28 and April 18. time plantings around the expected last-frost window for best survival.
When to Plant Bachelor's Button in Putnam County, MO
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.
Putnam County, Missouri is in USDA Zone 5b. The average last spring frost is April 18 and the first fall frost is October 16, giving you a growing season of approximately 181 days.
At an elevation of 1,185 feet, Putnam County receives approximately 40.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Bachelor's Button to ensure they mature before fall.
Putnam County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Bachelor's Button Planting Timeline — Putnam County, MO
Bachelor's Button Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 7 | Mar 7 – Mar 21 |
| Transplant Outdoors | April 18 | Apr 18 – May 2 |
| Direct Sow | March 28 | Mar 28 – Apr 18 |
| Bloom | June 20 | Jun 20 – Sep 5 |
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 | 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 5b
📆 Growing Season
181 days in Putnam County
Growing Tips for Putnam 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 Putnam County, MO?
Putnam County is in Zone 5b with an average last frost of April 18. Plan your Bachelor's Button planting based on this frost date — see the calendar above for exact timing.
What planting zone is Putnam County, MO?
Putnam County, Missouri is in USDA Hardiness Zone 5b. The average last spring frost is April 18 and first fall frost is October 16.
When should I plant Bachelor's Button in Putnam County, MO?
In Putnam County, MO, plant Bachelor's Button after the last frost (around April 18) and before the first frost (around October 16). Best results when soil holds above 50°F.
What growing zone is Putnam County, MO for Bachelor's Button?
Putnam 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 Putnam County's climate?
Yes — Bachelor's Button grows well in Putnam County's temperate climate. Putnam County averages a 181-day frost-free season, with last frost around April 18 and first frost around October 16.
Your Putnam County Garden Planner — Free
A 22-page printable planner built for Putnam 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.