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When to plant Ageratum in Cooper County, MO

Cooper County's spring Ageratum window runs April 10 through May 1. time plantings around the expected last-frost window for best survival.

When to Plant Ageratum in Cooper County, MO

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.

Cooper County, Missouri is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 25, giving you a growing season of approximately 198 days.

At an elevation of 1,035 feet, Cooper County receives approximately 35.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 88°F, providing good warmth for Ageratum during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Good for cutting
Cooper County, MO (Zone 6b) Moderate season
198 days
Last Spring Frost April 10
198 growing days
First Fall Frost October 25

Cooper County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Ageratum Planting Timeline — Cooper County, MO

Ageratum Planting Calendar

Activity When Date Range
Start Indoors February 20 Feb 20 – Mar 6
Transplant Outdoors April 10 Apr 10 – Apr 24
Direct Sow April 10 Apr 10 – May 1
Bloom June 5 Jun 5 – Sep 18

· 8" apart · Rows 10" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors
April Transplant Outdoors Direct Sow
May 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

198 days in Cooper County

Growing Tips for Cooper 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 Cooper County, MO?

Cooper County is in Zone 6b with an average last frost of April 10. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.

What planting zone is Cooper County, MO?

Cooper County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 10 and first fall frost is October 25.

When should I plant Ageratum in Cooper County, MO?

In Cooper County, MO, plant Ageratum after the last frost (around April 10) and before the first frost (around October 25). Best results when soil holds above 50°F.

What growing zone is Cooper County, MO for Ageratum?

Cooper 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 Cooper County's climate?

Yes — Ageratum grows well in Cooper County's temperate climate. Cooper County averages a 198-day frost-free season, with last frost around April 10 and first frost around October 25.

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A 22-page printable planner built for Cooper 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 Cooper County, MO. Local conditions may vary. Last updated: June 2026.

Sources & credits

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