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When to plant Ageratum in Carroll County, KY

Plant Ageratum in Carroll County, when soil hits 50°F — usually April 18. Continue planting through May 9 for the spring crop.

When to Plant Ageratum in Carroll County, KY

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.

Carroll County, Kentucky is in USDA Zone 6b. The average last spring frost is April 18 and the first fall frost is October 20, giving you a growing season of approximately 185 days.

At an elevation of 3,005 feet, Carroll County receives approximately 42.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Ageratum during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Good for cutting
Carroll County, KY (Zone 6b) Moderate season
185 days
Last Spring Frost April 18
185 growing days
First Fall Frost October 20

Carroll County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Ageratum Planting Timeline — Carroll County, KY

Ageratum Planting Calendar

Activity When Date Range
Start Indoors February 28 Feb 28 – Mar 14
Transplant Outdoors April 18 Apr 18 – May 2
Direct Sow April 18 Apr 18 – May 9
Bloom June 13 Jun 13 – Sep 26

· 8" apart · Rows 10" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
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

185 days in Carroll County

Growing Tips for Carroll 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 →

Frequently Asked Questions

When should I plant Ageratum in Carroll County, KY?

Carroll County is in Zone 6b with an average last frost of April 18. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.

What planting zone is Carroll County, KY?

Carroll County, Kentucky is in USDA Hardiness Zone 6b. The average last spring frost is April 18 and first fall frost is October 20.

When should I plant Ageratum in Carroll County, KY?

In Carroll County, KY, plant Ageratum after the last frost (around April 18) and before the first frost (around October 20). Best results when soil holds above 50°F.

What growing zone is Carroll County, KY for Ageratum?

Carroll County sits in USDA Zone 6b. Ageratum grows reliably in zones 3a through 11b, so it's a good fit here.

Can Ageratum grow in Carroll County's climate?

Yes — Ageratum grows well in Carroll County's temperate climate. Carroll County averages a 185-day frost-free season, with last frost around April 18 and first frost around October 20.

🌱

Your Carroll County Garden Planner — Free

A 22-page printable planner built for Carroll 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.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Carroll County, KY. Local conditions may vary. Last updated: June 2026.

Sources & credits

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