When to plant Ageratum in Elbert County, CO
Elbert County sits in cold Zone 5b. Plant Ageratum May 19–June 9 for the single annual harvest; the October 3 first frost closes the window.
When to Plant Ageratum in Elbert 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.
Elbert County, Colorado is in USDA Zone 5b. The average last spring frost is May 12 and the first fall frost is October 3, giving you a growing season of approximately 144 days.
At an elevation of 5,587 feet, Elbert County receives approximately 22.1 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Ageratum during the growing season.
Elbert County Soil Profile
Soil Type
Loam
Soil pH
6.2-7.7
Drainage
Well Drained
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 | — | 1.4" | 0" | ❄️ Dormant |
| Feb | — | 1.2" | 0" | ❄️ Dormant |
| Mar | — | 1.8" | 0" | ❄️ Dormant |
| Apr | — | 2.2" | 0" | ❄️ Dormant |
| May | 4.3" | 2.4" | 1.9" | 💧 Light watering |
| Jun | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Jul | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Aug | 4.3" | 2.3" | 2" | 💧 Light watering |
| Sep | 4.3" | 2" | 2.3" | 🚿 Regular watering |
| Oct | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Nov | — | 1.8" | 0" | ❄️ Dormant |
| Dec | — | 1.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Elbert County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Ageratum Planting Timeline — Elbert County, CO
Ageratum Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 24 | Mar 24 – Apr 7 |
| Transplant Outdoors | May 19 | May 19 – Jun 2 |
| Direct Sow | May 19 | May 19 – Jun 9 |
| Bloom | July 14 | Jul 14 – Oct 13 |
· 8" apart · Rows 10" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors |
| May | Transplant Outdoors Direct Sow |
| June | Transplant Outdoors Direct Sow |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| 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
144 days in Elbert County
Growing Tips for Elbert 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 →
Ageratum in Other Locations
Frequently Asked Questions
When should I plant Ageratum in Elbert County, CO?
Elbert County is in Zone 5b with an average last frost of May 12. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.
What planting zone is Elbert County, CO?
Elbert County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is May 12 and first fall frost is October 3.
When should I plant Ageratum in Elbert County, CO?
In Elbert County, CO, plant Ageratum after the last frost (around May 12) and before the first frost (around October 3). Best results when soil holds above 50°F.
What growing zone is Elbert County, CO for Ageratum?
Elbert 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 Elbert County's climate?
Yes — Ageratum grows well in Elbert County's temperate climate. Elbert County averages a 144-day frost-free season, with last frost around May 12 and first frost around October 3.
Your Elbert County Garden Planner — Free
A 22-page printable planner built for Elbert 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.