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When to plant Ageratum in Logan County County,

In Zone 6a (Logan County County), direct-sow Ageratum between April 15 and May 6 for spring, after the April 15 last-frost mark.

When to Plant Ageratum in Logan County, IL

Logan County, Illinois Zone 6a June

Logan County, Illinois gardeners: here's your June plan

Your garden in Logan County, Illinois is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost April 15
Avg. first frost October 16
Soil temp (4") 70°F
Watering Low
Pest pressure High
Daylight 14.8 hrs
  1. Time to start ageratum inside

    Label every cell. You will absolutely forget which is which otherwise.

  2. It's harvest week for ageratum

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

Before July arrives, get these ready
  • 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.

Logan County, Illinois is in USDA Zone 6a. The average last spring frost is April 15 and the first fall frost is October 16, giving you a growing season of approximately 184 days.

At an elevation of 1,132 feet, Logan County receives approximately 39.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Ageratum to ensure they mature before fall.

Annual Blooms in Multi-season Pollinator-friendly Good for cutting
Logan County, IL (Zone 6a) Moderate season
184 days
Last Spring Frost April 15
184 growing days
First Fall Frost October 16
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Logan County Soil Profile

Soil Type

Silt Loam

Soil pH

6-6.7

Drainage

Well Drained

Ageratum Planting Risk Windows

Early Start (70% safe) ✓ Fits season (29 days to spare)
Start indoors: Feb 19 Transplant: Apr 9 🌸 Bloom: Jun 4 – Sep 10
Recommended (50%) ✓ Fits season (30 days to spare)
Start indoors: Feb 25 Transplant: Apr 15 🌸 Bloom: Jun 10 – Sep 16
Safe Start (90%) ✓ Fits season (36 days to spare)
Start indoors: Mar 5 Transplant: Apr 23 🌸 Bloom: Jun 18 – Sep 24

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 Logan County

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

Soil pH

Your soil pH (6.0–6.7) is within Ageratum's preferred range (6.0–7.0).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.2%) — Ageratum will thrive.

How to Plant Ageratum

8"
Between Plants
10"
Between Rows

Succession Planting Ageratum

3
successive plantings in your 184-day season

Sow every 6.9 weeks. Last sowing by Aug 02 to harvest before frost.

Ageratum Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 146 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 1.6" 0" ❄️ Dormant
Feb 1.7" 0" ❄️ Dormant
Mar 2.6" 0" ❄️ Dormant
Apr 4.3" 3.6" 0.7" 💧 Light watering
May 4.3" 5" 0" ✅ Rainfall sufficient
Jun 4.3" 5.4" 0" ✅ Rainfall sufficient
Jul 4.3" 5" 0" ✅ Rainfall sufficient
Aug 4.3" 3.9" 0.4" 💧 Light watering
Sep 4.3" 3.5" 0.8" 💧 Light watering
Oct 4.3" 2.7" 1.6" 💧 Light watering
Nov 2.7" 0" ❄️ Dormant
Dec 2.4" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Logan 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 ~827 GDD — county provides 2,254 GDD Excellent fit

Ageratum Planting Timeline — Logan County, IL

Ageratum Planting Calendar

Activity When Date Range
Start Indoors February 25 Feb 25 – Mar 11
Transplant Outdoors April 15 Apr 15 – Apr 29
Direct Sow April 15 Apr 15 – May 6
Bloom June 10 Jun 10 – Sep 16

· 8" apart · Rows 10" apart

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

60–75 days

🧪 Soil pH

Needs 6–7 · Your soil: ideal

🗺️ USDA Zone

Zone 6a

📆 Growing Season

184 days in Logan County

Growing Tips for Ageratum in Logan County

Direct sow Ageratum outdoors after April 15 in Logan County when soil has warmed and frost danger has passed.

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 Logan County, IL?

Logan County is in Zone 6a with an average last frost of April 15. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.

What planting zone is Logan County, IL?

Logan County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 15 and first fall frost is October 16.

When should I plant Ageratum in Logan County County, ?

In Logan County County, , plant Ageratum after the last frost (around April 15) and before the first frost (around October 16). Best results when soil holds above 50°F.

What growing zone is Logan County County, for Ageratum?

Logan County County sits in USDA Zone 6a. Ageratum grows reliably in zones 3a through 11b, so it's a good fit here.

Can Ageratum grow in Logan County County's climate?

Yes — Ageratum grows well in Logan County County's temperate climate. Logan County County averages a 184-day frost-free season, with last frost around April 15 and first frost around October 16.

🌱

Your Logan County Garden Planner — Free

A 22-page printable planner built for Logan County (Zone 6a). 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 Logan County, IL. Local conditions may vary. Last updated: June 2026.

Sources & credits

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