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When to plant Ageratum in Mapleton, KS

Plant Ageratum in Mapleton from April 8 to April 29 in spring. Mapleton sits in USDA Zone 7a, with last frost around April 8 and first frost on October 25.

When to Plant Ageratum in Mapleton, KS

Bourbon County, Kansas Zone 7a July

What to do in July

A quick July briefing for Bourbon County, Kansas gardeners — what's urgent, what's next, and what can wait.

Avg. last frost April 8
Avg. first frost October 25
Soil temp (4") 81°F
Watering Moderate
Pest pressure High
Daylight 14.4 hrs
  1. Pick ageratum

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

To set up a strong August, 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.

Mapleton, Kansas is in USDA Zone 7a. The average last spring frost is April 8 and the first fall frost is October 25, giving you a growing season of approximately 200 days.

At an elevation of 438 feet, Bourbon County receives approximately 26 inches of rainfall annually with predominantly loam soil. Summer highs average 85°F, providing good warmth for Ageratum during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Good for cutting
Mapleton, KS (Zone 7a) Long season
200 days
Last Spring Frost April 8
200 growing days
First Fall Frost October 25

Mapleton Soil Profile

Soil Type

Loam

Soil pH

6.2-7.2

Drainage

Well Drained

Ageratum Planting Risk Windows

Early Start (70% safe) ✓ Fits season (32 days to spare)
Start indoors: Feb 19 Transplant: Apr 2 🌸 Bloom: May 28 – Sep 17
Recommended (50%) ✓ Fits season (32 days to spare)
Start indoors: Feb 25 Transplant: Apr 8 🌸 Bloom: Jun 3 – Sep 23
Safe Start (90%) ✓ Fits season (30 days to spare)
Start indoors: Mar 10 Transplant: Apr 21 🌸 Bloom: Jun 16 – Oct 6

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 Mapleton

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

Soil pH

Your soil pH (6.2–7.2) overlaps with Ageratum's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.8%). Annual compost additions will help Ageratum.

How to Plant Ageratum

8"
Between Plants
10"
Between Rows

Succession Planting Ageratum

3
successive plantings in your 200-day season

Sow every 6.9 weeks. Last sowing by Aug 11 to harvest before frost.

Ageratum Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 808 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 0.6" 0" ❄️ Dormant
Feb 0.8" 0" ❄️ Dormant
Mar 1.8" 0" ❄️ Dormant
Apr 4.3" 2.7" 1.6" 💧 Light watering
May 4.3" 4.2" 0.1" 💧 Light watering
Jun 4.3" 3.8" 0.5" 💧 Light watering
Jul 4.3" 3.2" 1.1" 💧 Light watering
Aug 4.3" 3.3" 1" 💧 Light watering
Sep 4.3" 2.4" 1.9" 💧 Light watering
Oct 4.3" 1.8" 2.5" 🚿 Regular watering
Nov 0.8" 0" ❄️ Dormant
Dec 0.6" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Bourbon 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 ~928 GDD — county provides 2,750 GDD Excellent fit

Ageratum Planting Timeline — Mapleton, KS

Ageratum Planting Calendar

Activity When Date Range
Start Indoors February 25 Feb 25 – Mar 11
Transplant Outdoors April 8 Apr 8 – Apr 22
Direct Sow April 8 Apr 8 – Apr 29
Bloom June 3 Jun 3 – Sep 23

· 8" apart · Rows 10" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

60–75 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

200 days in Bourbon County

Growing Tips for Ageratum in Mapleton

Direct sow Ageratum outdoors after April 08 in Bourbon 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 Mapleton, KS?

In Mapleton, KS, plant Ageratum after the last frost (around April 8) and before the first frost (around October 25). Best results when soil holds above 50°F.

What growing zone is Mapleton, KS for Ageratum?

Mapleton sits in USDA Zone 7a. Ageratum grows reliably in zones 3a through 11b, so it's a good fit here.

Can Ageratum grow in Mapleton's climate?

Yes — Ageratum grows well in Mapleton's temperate climate. Mapleton averages a 200-day frost-free season, with last frost around April 8 and first frost around October 25.

🌱

Your Bourbon County Garden Planner — Free

A 22-page printable planner built for Bourbon County (Zone 7a). 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 Bourbon County, KS. Local conditions may vary. Last updated: July 2026.