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When to plant Ageratum in Steuben County County,

Plant Ageratum in Steuben County County, when soil hits 50°F — usually April 26. Continue planting through May 17 for the spring crop.

When to Plant Ageratum in Steuben County, IN

Steuben County, Indiana Zone 6a June

Your June game plan for Steuben County, Indiana

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 26
Avg. first frost October 17
Soil temp (4") 70°F
Watering Low
Pest pressure High
Daylight 15 hrs
  1. Sow ageratum in trays indoors

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

  2. It's harvest week for ageratum

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

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.

Steuben County, Indiana is in USDA Zone 6a. The average last spring frost is April 26 and the first fall frost is October 17, giving you a growing season of approximately 174 days.

At an elevation of 760 feet, Steuben County receives approximately 38.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Ageratum during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Good for cutting
Steuben County, IN (Zone 6a) Moderate season
174 days
Last Spring Frost April 26
174 growing days
First Fall Frost October 17
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Steuben County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-7.2

Drainage

Well Drained

Ageratum Planting Risk Windows

Early Start (70% safe) ✓ Fits season (15 days to spare)
Start indoors: Mar 5 Transplant: Apr 23 🌸 Bloom: Jun 18 – Sep 24
Recommended (50%) ✓ Fits season (20 days to spare)
Start indoors: Mar 8 Transplant: Apr 26 🌸 Bloom: Jun 21 – Sep 27
Safe Start (90%) ✓ Fits season (14 days to spare)
Start indoors: Mar 26 Transplant: May 14 🌸 Bloom: Jul 9 – Oct 15

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 Steuben County

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

Soil pH

Your soil pH (5.8–7.2) overlaps with Ageratum's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.1%) — Ageratum will thrive.

How to Plant Ageratum

8"
Between Plants
10"
Between Rows

Succession Planting Ageratum

3
successive plantings in your 174-day season

Sow every 6.9 weeks. Last sowing by Aug 03 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 122 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 1.5" 0" ❄️ Dormant
Feb 1.8" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 4.3" 3.7" 0.6" 💧 Light watering
May 4.3" 4.9" 0" ✅ Rainfall sufficient
Jun 4.3" 5" 0" ✅ Rainfall sufficient
Jul 4.3" 3.8" 0.5" 💧 Light watering
Aug 4.3" 4.3" 0" ✅ Rainfall sufficient
Sep 4.3" 3.5" 0.8" 💧 Light watering
Oct 4.3" 3.1" 1.2" 💧 Light watering
Nov 2.5" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Steuben 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 ~1,029 GDD — county provides 2,653 GDD Excellent fit

Ageratum Planting Timeline — Steuben County, IN

Ageratum Planting Calendar

Activity When Date Range
Start Indoors March 8 Mar 8 – Mar 22
Transplant Outdoors April 26 Apr 26 – May 10
Direct Sow April 26 Apr 26 – May 17
Bloom June 21 Jun 21 – Sep 27

· 8" apart · Rows 10" apart

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors
April Transplant Outdoors Direct Sow
May Transplant Outdoors 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 6a

📆 Growing Season

174 days in Steuben County

Growing Tips for Ageratum in Steuben County

Direct sow Ageratum outdoors after April 26 in Steuben 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 Steuben County, IN?

Steuben County is in Zone 6a with an average last frost of April 26. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.

What planting zone is Steuben County, IN?

Steuben County, Indiana is in USDA Hardiness Zone 6a. The average last spring frost is April 26 and first fall frost is October 17.

When should I plant Ageratum in Steuben County, ?

In Steuben County, , plant Ageratum after the last frost (around April 26) and before the first frost (around October 17). Best results when soil holds above 50°F.

What growing zone is Steuben County, for Ageratum?

Steuben 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 Steuben County's climate?

Yes — Ageratum grows well in Steuben County's temperate climate. Steuben County averages a 174-day frost-free season, with last frost around April 26 and first frost around October 17.

🌱

Your Steuben County Garden Planner — Free

A 22-page printable planner built for Steuben 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 Steuben County, IN. 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.