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When to plant Ageratum in Jasper County County,

Jasper County County's spring Ageratum window runs April 13 through May 4. time plantings around the expected last-frost window for best survival.

When to Plant Ageratum in Jasper County, IL

Jasper County, Illinois Zone 6b June

June in the garden — Jasper County, Illinois

If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.

Avg. last frost April 13
Avg. first frost October 20
Soil temp (4") 73°F
Watering Low
Pest pressure High
Daylight 14.7 hrs
  1. Fire up the seed-starting tray: ageratum

    Give them 6–8 weeks indoors before the last frost and you'll transplant into warm soil with seedlings that are already leaping.

  2. Pick ageratum

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

To set up a strong July, finish these tasks
  • 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.

Jasper County, Illinois is in USDA Zone 6b. The average last spring frost is April 13 and the first fall frost is October 20, giving you a growing season of approximately 190 days.

At an elevation of 1,384 feet, Jasper County receives approximately 35 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Ageratum during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Good for cutting
Jasper County, IL (Zone 6b) Moderate season
190 days
Last Spring Frost April 13
190 growing days
First Fall Frost October 20
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Jasper County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.3

Drainage

Well Drained

Ageratum Planting Risk Windows

Early Start (70% safe) ✓ Fits season (29 days to spare)
Start indoors: Feb 17 Transplant: Apr 7 🌸 Bloom: Jun 2 – Sep 15
Recommended (50%) ✓ Fits season (29 days to spare)
Start indoors: Feb 23 Transplant: Apr 13 🌸 Bloom: Jun 8 – Sep 21
Safe Start (90%) ✓ Fits season (26 days to spare)
Start indoors: Mar 9 Transplant: Apr 27 🌸 Bloom: Jun 22 – Oct 5

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 Jasper County

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

Soil pH

Your soil pH (5.9–7.3) overlaps with Ageratum's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.5%) — Ageratum will thrive.

How to Plant Ageratum

8"
Between Plants
10"
Between Rows

Succession Planting Ageratum

3
successive plantings in your 190-day season

Sow every 6.9 weeks. Last sowing by Aug 06 to harvest before frost.

Ageratum Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 459 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 1.4" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.4" 0" ❄️ Dormant
Apr 4.3" 3.1" 1.2" 💧 Light watering
May 4.3" 4.1" 0.2" 💧 Light watering
Jun 4.3" 4.7" 0" ✅ Rainfall sufficient
Jul 4.3" 3.3" 1" 💧 Light watering
Aug 4.3" 3.5" 0.8" 💧 Light watering
Sep 4.3" 3.4" 0.9" 💧 Light watering
Oct 4.3" 3" 1.3" 💧 Light watering
Nov 2.5" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Jasper 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 ~1,232 GDD — county provides 3,467 GDD Excellent fit

Ageratum Planting Timeline — Jasper County, IL

Ageratum Planting Calendar

Activity When Date Range
Start Indoors February 23 Feb 23 – Mar 9
Transplant Outdoors April 13 Apr 13 – Apr 27
Direct Sow April 13 Apr 13 – May 4
Bloom June 8 Jun 8 – Sep 21

· 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: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

190 days in Jasper County

Growing Tips for Ageratum in Jasper County

Direct sow Ageratum outdoors after April 13 in Jasper 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 Jasper County, IL?

Jasper County is in Zone 6b with an average last frost of April 13. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jasper County, IL?

Jasper County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 13 and first fall frost is October 20.

When should I plant Ageratum in Jasper County County, ?

In Jasper County County, , plant Ageratum after the last frost (around April 13) and before the first frost (around October 20). Best results when soil holds above 50°F.

What growing zone is Jasper County County, for Ageratum?

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

Can Ageratum grow in Jasper County County's climate?

Yes — Ageratum grows well in Jasper County County's temperate climate. Jasper County County averages a 190-day frost-free season, with last frost around April 13 and first frost around October 20.

🌱

Your Jasper County Garden Planner — Free

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

Sources & credits

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