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When to plant Ageratum in Madison County, AL

Ageratum planted in Madison County between March 30 and April 20 matures in 60–75 days — well before the October 31 first frost.

When to Plant Ageratum in Madison County, AL

Madison County, Alabama Zone 8a June

Top priorities for Madison County, Alabama gardeners in June

June is a pivotal month for Madison County, Alabama gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost April 6
Avg. first frost October 31
Soil temp (4") 76°F
Watering Low
Pest pressure High
Daylight 14.3 hrs
  1. Start harvesting ageratum

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

Coming up in July — 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.

Madison County, Alabama is in USDA Zone 8a. The average last spring frost is April 6 and the first fall frost is October 31, giving you a growing season of approximately 208 days.

At an elevation of 286 feet, Madison County receives approximately 55.3 inches of rainfall annually with predominantly clay loam soil. Summer highs average 90°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
Madison County, AL (Zone 8a) Long season
208 days
Last Spring Frost April 6
208 growing days
First Fall Frost October 31

Madison County Soil Profile

Soil Type

Clay Loam

Soil pH

5.6-6.7

Drainage

Well Drained

Ageratum Planting Risk Windows

Early Start (70% safe) ✓ Fits season (21 days to spare)
Start indoors: Feb 13 Transplant: Mar 20 🌸 Bloom: May 15 – Oct 2
Recommended (50%) ✓ Fits season (19 days to spare)
Start indoors: Feb 23 Transplant: Mar 30 🌸 Bloom: May 25 – Oct 12
Safe Start (90%) ✓ Fits season (19 days to spare)
Start indoors: Mar 8 Transplant: Apr 12 🌸 Bloom: Jun 7 – Oct 25

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 Madison County

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

Soil pH

Your soil pH (5.6–6.7) overlaps with Ageratum's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.7%). Annual compost additions will help Ageratum.

How to Plant Ageratum

8"
Between Plants
10"
Between Rows

Succession Planting Ageratum

4
successive plantings in your 208-day season

Sow every 6.9 weeks. Last sowing by Aug 17 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

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 4.9" 0" ❄️ Dormant
Feb 4.3" 0" ❄️ Dormant
Mar 5.6" 0" ❄️ Dormant
Apr 4.3" 4" 0.3" 💧 Light watering
May 4.3" 4" 0.3" 💧 Light watering
Jun 4.3" 4.2" 0.1" 💧 Light watering
Jul 4.3" 6.6" 0" ✅ Rainfall sufficient
Aug 4.3" 4.8" 0" ✅ Rainfall sufficient
Sep 4.3" 3.8" 0.5" 💧 Light watering
Oct 4.3" 3.5" 0.8" 💧 Light watering
Nov 4.8" 0" ❄️ Dormant
Dec 4.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Madison 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 ~1,181 GDD — county provides 3,640 GDD Excellent fit

Ageratum Planting Timeline — Madison County, AL

Ageratum Planting Calendar

Activity When Date Range
Start Indoors February 23 Feb 23 – Mar 9
Transplant Outdoors March 30 Mar 30 – Apr 13
Direct Sow March 30 Mar 30 – Apr 20
Bloom May 25 May 25 – Oct 12

· 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 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: acceptable

🗺️ USDA Zone

Zone 8a

📆 Growing Season

208 days in Madison County

Growing Tips for Ageratum in Madison County

Direct sow Ageratum outdoors after April 06 in Madison County when soil has warmed and frost danger has passed.

With Madison 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 Madison County, AL?

Madison County is in Zone 8a with an average last frost of April 6. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.

What planting zone is Madison County, AL?

Madison County, Alabama is in USDA Hardiness Zone 8a. The average last spring frost is April 6 and first fall frost is October 31.

When should I plant Ageratum in Madison County, AL?

In Madison County, AL, plant Ageratum after the last frost (around April 6) and before the first frost (around October 31). Best results when soil holds above 50°F.

What growing zone is Madison County, AL for Ageratum?

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

Can Ageratum grow in Madison County's climate?

Yes — Ageratum grows well in Madison County's temperate climate. Madison County averages a 208-day frost-free season, with last frost around April 6 and first frost around October 31.

🌱

Your Madison County Garden Planner — Free

A 22-page printable planner built for Madison County (Zone 8a). 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 Madison County, AL. Local conditions may vary. Last updated: June 2026.

Sources & credits

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