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When to plant Ageratum in Conception Junction, MO

In Conception Junction, plant Ageratum in spring between April 29 and May 20, once soil temps hold above 50°F. Conception Junction's last frost averages April 22, so time plantings around the expected last-frost window for best survival. For a fall crop, sow between and — roughly 60–75 days before the first frost on October 13.

When to Plant Ageratum in Conception Junction, MO

Nodaway County, Missouri Zone 5b July

Your July gardening checklist

Welcome to July in Zone 5b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost April 22
Avg. first frost October 13
Soil temp (4") 76°F
Watering Low
Pest pressure High
Daylight 14.6 hrs
  1. Basket week: ageratum

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

A few tasks this July that'll pay off in August
  • 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.

Conception Junction, Missouri is in USDA Zone 5b. The average last spring frost is April 22 and the first fall frost is October 13, giving you a growing season of approximately 174 days.

At an elevation of 950 feet, Nodaway County receives approximately 42 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
Conception Junction, MO (Zone 5b) Moderate season
174 days
Last Spring Frost April 22
174 growing days
First Fall Frost October 13

Conception Junction Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.5

Drainage

Well Drained

Ageratum Planting Risk Windows

Early Start (70% safe) ✓ Fits season (20 days to spare)
Start indoors: Feb 25 Transplant: Apr 22 🌸 Bloom: Jun 17 – Sep 16
Recommended (50%) ✓ Fits season (20 days to spare)
Start indoors: Mar 4 Transplant: Apr 29 🌸 Bloom: Jun 24 – Sep 23
Safe Start (90%) ✓ Fits season (20 days to spare)
Start indoors: Mar 18 Transplant: May 13 🌸 Bloom: Jul 8 – Oct 7

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 Conception Junction

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

Soil pH

Your soil pH (5.7–6.5) overlaps with Ageratum's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Ageratum.

Organic Matter

Organic matter is moderate (3.2%). Annual compost additions will help Ageratum.

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 Jul 30 to harvest before frost.

Ageratum Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/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 1.9" 0" ❄️ Dormant
Feb 2.1" 0" ❄️ Dormant
Mar 3" 0" ❄️ Dormant
Apr 4.3" 4.4" 0" ✅ Rainfall sufficient
May 4.3" 4.8" 0" ✅ Rainfall sufficient
Jun 4.3" 5.3" 0" ✅ Rainfall sufficient
Jul 4.3" 4.1" 0.2" 💧 Light watering
Aug 4.3" 3.8" 0.5" 💧 Light watering
Sep 4.3" 4.1" 0.2" 💧 Light watering
Oct 4.3" 3.7" 0.6" 💧 Light watering
Nov 2.6" 0" ❄️ Dormant
Dec 2.4" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Nodaway 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 2,131 GDD Excellent fit

Ageratum Planting Timeline — Conception Junction, MO

Ageratum Planting Calendar

Activity When Date Range
Start Indoors March 4 Mar 4 – Mar 18
Transplant Outdoors April 29 Apr 29 – May 13
Direct Sow April 29 Apr 29 – May 20
Bloom June 24 Jun 24 – Sep 23

· 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

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 5b

📆 Growing Season

174 days in Nodaway County

Growing Tips for Ageratum in Conception Junction

Direct sow Ageratum outdoors after April 22 in Nodaway 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 →

When should I plant Ageratum in Conception Junction, MO?

In Conception Junction, MO, plant Ageratum after the last frost (around April 22) and before the first frost (around October 13). Best results when soil holds above 50°F.

What growing zone is Conception Junction, MO for Ageratum?

Conception Junction sits in USDA Zone 5b. Ageratum grows reliably in zones 3a through 11b, so it's a good fit here.

Can Ageratum grow in Conception Junction's climate?

Yes — Ageratum grows well in Conception Junction's temperate climate. Conception Junction averages a 174-day frost-free season, with last frost around April 22 and first frost around October 13.

🌱

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A 22-page printable planner built for Nodaway County (Zone 5b). 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 Nodaway County, MO. Local conditions may vary. Last updated: July 2026.