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When to plant Ageratum in Clarke County, GA

Ageratum planted in Clarke County between March 12 and April 2 matures in 60–75 days — well before the November 10 first frost.

When to Plant Ageratum in Clarke County, GA

Clarke County, Georgia Zone 8b July

Top priorities for Clarke County, Georgia gardeners in July

Welcome to July in Zone 8b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost March 26
Avg. first frost November 10
Soil temp (4") 88°F
Watering Low
Pest pressure High
Daylight 14.1 hrs
  1. Bring in the ageratum

    If you can't use it all right away, check the food-preservation section of your planner.

Coming up in August — start thinking about
  • First harvests: ageratum

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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.

Clarke County, Georgia is in USDA Zone 8b. The average last spring frost is March 26 and the first fall frost is November 10, giving you a growing season of approximately 229 days.

At an elevation of 286 feet, Clarke County receives approximately 60.1 inches of rainfall annually with predominantly clay loam soil. Summer highs average 94°F, providing good warmth for Ageratum during the growing season. Clay soil retains moisture well for Ageratum, but amend with compost to improve drainage and prevent root rot. 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
Clarke County, GA (Zone 8b) Long season
229 days
Last Spring Frost March 26
229 growing days
First Fall Frost November 10

Clarke County Soil Profile

Soil Type

Clay Loam

Soil pH

5.3-6.5

Drainage

Well Drained

Ageratum Planting Risk Windows

Early Start (70% safe) ✓ Fits season (32 days to spare)
Start indoors: Feb 4 Transplant: Mar 4 🌸 Bloom: Apr 29 – Sep 30
Recommended (50%) ✓ Fits season (33 days to spare)
Start indoors: Feb 12 Transplant: Mar 12 🌸 Bloom: May 7 – Oct 8
Safe Start (90%) ✓ Fits season (32 days to spare)
Start indoors: Mar 5 Transplant: Apr 2 🌸 Bloom: May 28 – Oct 29

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Clarke County

How your county's soil matches Ageratum's growing requirements.

Soil pH

Your soil pH (5.3–6.5) is more acidic than Ageratum prefers (6.0–7.0). Add garden lime to raise pH.

Soil Texture

The clay loam soil in Clarke County is excellent for Ageratum — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Ageratum.

How to Plant Ageratum

8"
Between Plants
10"
Between Rows

Succession Planting Ageratum

4
successive plantings in your 229-day season

Sow every 6.9 weeks. Last sowing by Aug 27 to harvest before frost.

Ageratum Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 4.4" 0" ❄️ Dormant
Feb 4.5" 0" ❄️ Dormant
Mar 4.3" 5.7" 0" ✅ Rainfall sufficient
Apr 4.3" 4.4" 0" ✅ Rainfall sufficient
May 4.3" 4.5" 0" ✅ Rainfall sufficient
Jun 4.3" 5.9" 0" ✅ Rainfall sufficient
Jul 4.3" 6.9" 0" ✅ Rainfall sufficient
Aug 4.3" 6.3" 0" ✅ Rainfall sufficient
Sep 4.3" 3.9" 0.4" 💧 Light watering
Oct 4.3" 3.8" 0.5" 💧 Light watering
Nov 4.3" 4.9" 0" ✅ Rainfall sufficient
Dec 5" 0" ❄️ Dormant

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

Ageratum Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Ageratum needs ~1,384 GDD — county provides 4,694 GDD Excellent fit

Ageratum Planting Timeline — Clarke County, GA

Ageratum Planting Calendar

Activity When Date Range
Start Indoors February 12 Feb 12 – Feb 26
Transplant Outdoors March 12 Mar 12 – Mar 26
Direct Sow March 12 Mar 12 – Apr 2
Bloom May 7 May 7 – Oct 8

· 8" apart · Rows 10" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

60–75 days

🧪 Soil pH

Needs 6–7 · Your soil: too_acidic

🗺️ USDA Zone

Zone 8b

📆 Growing Season

229 days in Clarke County

Growing Tips for Ageratum in Clarke County

Direct sow Ageratum outdoors after March 26 in Clarke County when soil has warmed and frost danger has passed.

With Clarke County's clay soil (29% clay), work in 3-4 inches of compost before planting Ageratum. Avoid tilling when soil is wet to prevent compaction.

Common pests for Ageratum in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

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 Clarke County, GA?

Clarke County is in Zone 8b with an average last frost of March 26. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.

What planting zone is Clarke County, GA?

Clarke County, Georgia is in USDA Hardiness Zone 8b. The average last spring frost is March 26 and first fall frost is November 10.

When should I plant Ageratum in Clarke County, GA?

In Clarke County, GA, plant Ageratum after the last frost (around March 26) and before the first frost (around November 10). Best results when soil holds above 50°F.

What growing zone is Clarke County, GA for Ageratum?

Clarke County sits in USDA Zone 8b. Ageratum grows reliably in zones 3a through 11b, so it's a good fit here.

Can Ageratum grow in Clarke County's climate?

Yes — Ageratum grows well in Clarke County's temperate climate. Clarke County averages a 229-day frost-free season, with last frost around March 26 and first frost around November 10.

🌱

Your Clarke County Garden Planner — Free

A 22-page printable planner built for Clarke County (Zone 8b). 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 Clarke County, GA. Local conditions may vary. Last updated: July 2026.

Sources & credits

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