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When to plant Ageratum in Ouray County, CO

In Ouray County, Ageratum is a spring-only crop. Plant June 25–July 16 once soil hits 50°F.

When to Plant Ageratum in Ouray County, CO

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.

Ouray County, Colorado is in USDA Zone 5b. The average last spring frost is June 18 and the first fall frost is September 10, giving you a growing season of approximately 84 days.

At an elevation of 7,449 feet, Ouray County receives approximately 12.6 inches of rainfall annually with predominantly loam soil. Summer highs average 86°F, providing good warmth for Ageratum during the growing season. With low rainfall, drip irrigation is essential for growing Ageratum successfully. Mulch heavily to conserve soil moisture.

Annual Blooms in Multi-season Pollinator-friendly Good for cutting
Ouray County, CO (Zone 5b) Very short season
84 days
Last Spring Frost June 18
84 growing days
First Fall Frost September 10

Ouray County Soil Profile

Soil Type

Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Ageratum Planting Timeline — Ouray County, CO

Ageratum Planting Calendar

Activity When Date Range
Start Indoors April 30 Apr 30 – May 14
Transplant Outdoors June 25 Jun 25 – Jul 9
Direct Sow June 25 Jun 25 – Jul 16
Bloom August 20 Aug 20 – Nov 19

· 8" apart · Rows 10" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

60–75 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5b

📆 Growing Season

84 days in Ouray County

Growing Tips for Ouray County

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 Ouray County, CO?

Ouray County is in Zone 5b with an average last frost of June 18. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.

What planting zone is Ouray County, CO?

Ouray County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is June 18 and first fall frost is September 10.

When should I plant Ageratum in Ouray County, CO?

In Ouray County, CO, plant Ageratum after the last frost (around June 18) and before the first frost (around September 10). Best results when soil holds above 50°F.

What growing zone is Ouray County, CO for Ageratum?

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

Can Ageratum grow in Ouray County's climate?

Yes — Ageratum grows well in Ouray County's temperate climate. Ouray County averages a 84-day frost-free season, with last frost around June 18 and first frost around September 10.

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Your Ouray County Garden Planner — Free

A 22-page printable planner built for Ouray 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 Ouray County, CO. Local conditions may vary. Last updated: July 2026.

Sources & credits

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