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When to Plant Ageratum in Jackson County, TX

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.

Jackson County, Texas is in USDA Zone 9b. The average last spring frost is February 21 and the first fall frost is December 5, giving you a growing season of approximately 287 days.

At an elevation of 286 feet, Jackson County receives approximately 64.3 inches of rainfall annually with predominantly loam soil. Summer highs average 103°F, so Ageratum may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Ageratum root diseases.

Annual Blooms in Multi-season Pollinator-friendly Good for cutting
Jackson County, TX (Zone 9b) Year-round
287 days
Last Spring Frost February 21
287 growing days
First Fall Frost December 5
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Jackson County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.2

Drainage

Well Drained

Monthly Watering Guide for Ageratum

Ageratum needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Ageratum Needs Rainfall You Supplement Action
Jan 1.7" 0" ❄️ Dormant
Feb 4.3" 2.1" 2.2" 🚿 Regular watering
Mar 4.3" 3.9" 0.4" 💧 Light watering
Apr 4.3" 6.5" 0" ✅ Rainfall sufficient
May 4.3" 9" 0" ✅ Rainfall sufficient
Jun 4.3" 10.4" 0" ✅ Rainfall sufficient
Jul 4.3" 7.9" 0" ✅ Rainfall sufficient
Aug 4.3" 8" 0" ✅ Rainfall sufficient
Sep 4.3" 6" 0" ✅ Rainfall sufficient
Oct 4.3" 4.8" 0" ✅ Rainfall sufficient
Nov 4.3" 2.3" 2" 💧 Light watering
Dec 4.3" 1.7" 2.6" 🚿 Regular watering

Water needs are for active growing months only (Feb–Dec in Jackson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Ageratum Planting Timeline — Jackson County, TX

Ageratum Planting Calendar

Activity When Date Range
Start Indoors January 10 Jan 10 – Jan 24
Transplant Outdoors January 31 Jan 31 – Feb 14
Direct Sow January 31 Jan 31 – Feb 21
Bloom March 28 Mar 28 – Sep 26

· 8" apart · Rows 10" apart

Month-by-Month Timeline

MonthActivities
January Start Indoors Transplant Outdoors Direct Sow
February Transplant Outdoors Direct Sow
March Bloom
April Bloom
May Bloom
June Bloom
July Bloom
August Bloom
September Bloom
October
November
December
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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 9b

📆 Growing Season

287 days in Jackson County

Growing Tips for Jackson 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 Jackson County, TX?

Jackson County is in Zone 9b with an average last frost of February 21. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jackson County, TX?

Jackson County, Texas is in USDA Hardiness Zone 9b. The average last spring frost is February 21 and first fall frost is December 5.

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Your Jackson County Garden Planner — Free

A 22-page printable planner built for Jackson County (Zone 9b). 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 Jackson County, TX. Local conditions may vary. Last updated: June 2026.

Sources & credits

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