Blog

When to Plant Ageratum in Louisiana

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.

Louisiana spans USDA hardiness zones 8b, 9a, 9b (with planting data available), so planting dates vary by your location within the state. Click your zone below for the most accurate dates.

Find Your County

Click your county for exact Ageratum planting dates based on your local frost dates.

Ageratum Planting Calendar for Louisiana

Zone 8b ~276 day growing season · Full guide →

Last frost: February 25 · First frost: November 28 · 276 day season

Activity When Date Range
Start Indoors January 14 Jan 14 – Jan 28
Transplant Outdoors February 11 Feb 11 – Feb 25
Direct Sow February 11 Feb 11 – Mar 4
Bloom April 8 Apr 8 – Sep 9
Zone 9a ~303 day growing season · Full guide →

Last frost: February 10 · First frost: December 10 · 303 day season

Activity When Date Range
Start Indoors December 30 Dec 30 – Jan 13
Transplant Outdoors January 27 Jan 27 – Feb 10
Direct Sow January 27 Jan 27 – Feb 17
Bloom March 24 Mar 24 – Sep 8
Zone 9b ~329 day growing season · Full guide →

Last frost: January 25 · First frost: December 20 · 329 day season

Activity When Date Range
Start Indoors December 14 Dec 14 – Dec 28
Transplant Outdoors January 4 Jan 4 – Jan 18
Direct Sow January 4 Jan 4 – Jan 25
Bloom March 1 Mar 1 – Aug 30

Growing Tips for Louisiana

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.

Frequently Asked Questions

When should I plant Ageratum in Louisiana?

Planting dates for Ageratum in Louisiana depend on your USDA zone. Louisiana spans zones 8b, 9a, 9b. Check the planting calendar above for your specific zone's frost dates and planting windows.

What zone is Louisiana for planting?

Louisiana contains USDA hardiness zones 8b, 9a, 9b. Your specific zone depends on your location within the state — northern and higher-elevation areas are in colder zones, while southern and coastal areas are warmer.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Last updated: June 2026.