Blog

When to Plant Ageratum in Hardeman County, TN

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.

Hardeman County, Tennessee is in USDA Zone 7b. The average last spring frost is March 30 and the first fall frost is October 30, giving you a growing season of approximately 214 days.

At an elevation of 3,185 feet, Hardeman County receives approximately 48.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 92°F, providing good warmth for Ageratum during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Good for cutting
Hardeman County, TN (Zone 7b) Long season
214 days
Last Spring Frost March 30
214 growing days
First Fall Frost October 30

Hardeman County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Ageratum Planting Timeline — Hardeman County, TN

Ageratum Planting Calendar

Activity When Date Range
Start Indoors February 16 Feb 16 – Mar 2
Transplant Outdoors March 30 Mar 30 – Apr 13
Direct Sow March 30 Mar 30 – Apr 20
Bloom May 25 May 25 – Sep 28

· 8" apart · Rows 10" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors Transplant Outdoors Direct Sow
April Transplant Outdoors Direct Sow
May Bloom
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 7b

📆 Growing Season

214 days in Hardeman County

Growing Tips for Hardeman 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 Hardeman County, TN?

Hardeman County is in Zone 7b with an average last frost of March 30. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.

What planting zone is Hardeman County, TN?

Hardeman County, Tennessee is in USDA Hardiness Zone 7b. The average last spring frost is March 30 and first fall frost is October 30.

🌱

Your Hardeman County Garden Planner — Free

A 22-page printable planner built for Hardeman County (Zone 7b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.