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When to plant Ageratum in Cheyenne County County,

Cheyenne County County's climate puts the Ageratum spring window between May 2 and May 23. time plantings around the expected last-frost window for best survival.

When to Plant Ageratum in Cheyenne County, CO

Cheyenne County, Colorado Zone 6a June

Your June game plan for Cheyenne County, Colorado

We've pulled the most time-sensitive tasks for Cheyenne County, Colorado this June and put them front and centre. Tackle them in order.

Avg. last frost May 2
Avg. first frost October 11
Soil temp (4") 47°F
Watering High
Pest pressure High
Daylight 14.7 hrs
  1. Start ageratum under lights

    Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.

  2. Start harvesting ageratum

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

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

Cheyenne County, Colorado is in USDA Zone 6a. The average last spring frost is May 2 and the first fall frost is October 11, giving you a growing season of approximately 162 days.

At an elevation of 7,824 feet, Cheyenne County receives approximately 21.3 inches of rainfall annually with predominantly loam soil. Summer highs average 86°F, providing good warmth for Ageratum during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Good for cutting
Cheyenne County, CO (Zone 6a) Moderate season
162 days
Last Spring Frost May 2
162 growing days
First Fall Frost October 11
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Cheyenne County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.8

Drainage

Well Drained

Ageratum Planting Risk Windows

Early Start (70% safe) ✓ Fits season (8 days to spare)
Start indoors: Mar 8 Transplant: Apr 26 🌸 Bloom: Jun 21 – Sep 27
Recommended (50%) ✓ Fits season (8 days to spare)
Start indoors: Mar 14 Transplant: May 2 🌸 Bloom: Jun 27 – Oct 3
Safe Start (90%) ✓ Fits season (8 days to spare)
Start indoors: Mar 28 Transplant: May 16 🌸 Bloom: Jul 11 – Oct 17

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 Cheyenne County

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

Soil pH

Your soil pH (6.8–7.8) is more alkaline than Ageratum prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

The loam soil in Cheyenne 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 (2.5%). Annual compost additions will help Ageratum.

How to Plant Ageratum

8"
Between Plants
10"
Between Rows

Succession Planting Ageratum

3
successive plantings in your 162-day season

Sow every 6.9 weeks. Last sowing by Jul 28 to harvest before frost.

Ageratum Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.9″/week
Watering frequency 2-3 times/week
Season total 1,294 gal / 100 sq ft
Drought risk

Water stress score is 10/10 — 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 1.6" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 1.9" 0" ❄️ Dormant
Apr 1.9" 0" ❄️ Dormant
May 4.3" 2.6" 1.7" 💧 Light watering
Jun 4.3" 1.6" 2.7" 🚿 Regular watering
Jul 4.3" 1.6" 2.7" 🚿 Regular watering
Aug 4.3" 2.2" 2.1" 💧 Light watering
Sep 4.3" 1.6" 2.7" 🚿 Regular watering
Oct 4.3" 2.1" 2.2" 🚿 Regular watering
Nov 1.6" 0" ❄️ Dormant
Dec 1.3" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Cheyenne 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 ~979 GDD — county provides 2,349 GDD Excellent fit

Ageratum Planting Timeline — Cheyenne County, CO

Ageratum Planting Calendar

Activity When Date Range
Start Indoors March 14 Mar 14 – Mar 28
Transplant Outdoors May 2 May 2 – May 16
Direct Sow May 2 May 2 – May 23
Bloom June 27 Jun 27 – Oct 3

· 8" apart · Rows 10" apart

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 2-3 times/week

📅 Days to Maturity

60–75 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 6a

📆 Growing Season

162 days in Cheyenne County

Growing Tips for Ageratum in Cheyenne County

Direct sow Ageratum outdoors after May 02 in Cheyenne 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.

Cheyenne County receives only 21" of rain annually. Ageratum needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

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 Cheyenne County, CO?

Cheyenne County is in Zone 6a with an average last frost of May 2. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.

What planting zone is Cheyenne County, CO?

Cheyenne County, Colorado is in USDA Hardiness Zone 6a. The average last spring frost is May 2 and first fall frost is October 11.

When should I plant Ageratum in Cheyenne County, ?

In Cheyenne County, , plant Ageratum after the last frost (around May 2) and before the first frost (around October 11). Best results when soil holds above 50°F.

What growing zone is Cheyenne County, for Ageratum?

Cheyenne 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 Cheyenne County's climate?

Yes — Ageratum grows well in Cheyenne County's temperate climate. Cheyenne County averages a 162-day frost-free season, with last frost around May 2 and first frost around October 11.

🌱

Your Cheyenne County Garden Planner — Free

A 22-page printable planner built for Cheyenne 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 Cheyenne County, CO. 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.