When to Plant Ageratum in Butler County, OH
Ageratum (Ageratum houstonianum), the floss flower, produces clusters of fluffy, powder-puff blooms in the rare sky-blue and lavender tones difficult to find among warm-season annuals. Compact mounding habit makes it ideal as a front-of-border edging plant. Blooms from early summer through fall with minimal deadheading; heat and humidity tolerant once established.
Butler County, Ohio is in USDA Zone 6b. The average last spring frost is April 20 and the first fall frost is October 21, giving you a growing season of approximately 184 days.
At an elevation of 704 feet, Butler County receives approximately 37.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Ageratum during the growing season.
Butler County Soil Profile
Soil Type
Silt Loam
Soil pH
6.0-7.0
Drainage
Well Drained
Ageratum Planting Timeline — Butler County, OH
Ageratum Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 2 | Mar 2 – Mar 16 |
| Transplant Outdoors | April 20 | Apr 20 – May 4 |
| Direct Sow | April 20 | Apr 20 – May 11 |
| Bloom | June 15 | Jun 15 – Sep 28 |
· 8" apart · Rows 10" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Moderate — regular watering
📅 Days to Maturity
60–75 days
🧪 Soil pH
Needs 6–7 · Your soil: N/A
🗺️ USDA Zone
Zone 6b
📆 Growing Season
184 days in Butler County
Growing Tips for Butler County
Start seeds indoors 6–8 weeks before last frost — do not cover seed; it needs light to germinate. Can be direct-sown after last frost once soil warms to 60°F. Transplant or thin to proper spacing after frost danger passes. Deadheading isn't strictly required but tidying spent clusters improves appearance. Provide consistent moisture; drought causes premature setting. Avoid deep shade — blooms best in full sun to light afternoon shade.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Ageratum in Other Locations
Frequently Asked Questions
When should I plant Ageratum in Butler County, OH?
Butler County is in Zone 6b with an average last frost of April 20. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.
What planting zone is Butler County, OH?
Butler County, Ohio is in USDA Hardiness Zone 6b. The average last spring frost is April 20 and first fall frost is October 21.
Your Butler County Garden Planner — Free
A 22-page printable planner built for Butler 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.