When to plant Ageratum in Jackson County County,
Plant Ageratum in Jackson County County, between June 20 and July 11 — the only viable window. Zone 4b's short season (83 frost-free days) rules out a fall crop.
When to Plant Ageratum in Jackson County, CO
Top priorities for Jackson County, Colorado gardeners in June
Welcome to June in Zone 4b. These are the moves that will have the biggest impact on your growing season.
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Move ageratum from tray to bed
Frost risk is low now in Jackson County, Colorado. If you've been covering beds overnight, you can stop.
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Plant ageratum from seed, right in the garden
Keep the top inch of soil moist until germination — a gentle morning watering for 5–7 days does the job.
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.
Jackson County, Colorado is in USDA Zone 4b. The average last spring frost is June 13 and the first fall frost is September 4, giving you a growing season of approximately 83 days.
At an elevation of 5,388 feet, Jackson County receives approximately 20.9 inches of rainfall annually with predominantly loam soil. Summer highs average 80°F, so choose short-season varieties of Ageratum to ensure they mature before fall.
Jackson County Soil Profile
Soil Type
Loam
Soil pH
6.6-8.1
Drainage
Well Drained
Ageratum Planting Risk Windows
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 Jackson County
How your county's soil matches Ageratum's growing requirements.
Soil pH
Your soil pH (6.6–8.1) is more alkaline than Ageratum prefers (6.0–7.0). Add sulfur or peat moss to lower pH.
Soil Texture
The loam soil in Jackson County is excellent for Ageratum — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.2%). Annual compost additions will help Ageratum.
How to Plant Ageratum
Ageratum Water Budget
Water stress score is 6/10 — 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 | — | 1.1" | 0" | ❄️ Dormant |
| Mar | — | 1.9" | 0" | ❄️ Dormant |
| Apr | — | 2.3" | 0" | ❄️ Dormant |
| May | — | 2.2" | 0" | ❄️ Dormant |
| Jun | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Jul | 4.3" | 1.7" | 2.6" | 🚿 Regular watering |
| Aug | 4.3" | 2.5" | 1.8" | 💧 Light watering |
| Sep | 4.3" | 1.5" | 2.8" | 🚿 Regular watering |
| Oct | — | 2.1" | 0" | ❄️ Dormant |
| Nov | — | 1.4" | 0" | ❄️ Dormant |
| Dec | — | 1.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Jun–Sep in Jackson 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 Planting Timeline — Jackson County, CO
Ageratum Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | April 25 | Apr 25 – May 9 |
| Transplant Outdoors | June 20 | Jun 20 – Jul 4 |
| Direct Sow | June 20 | Jun 20 – Jul 11 |
| Bloom | August 15 | Aug 15 – Oct 31 |
· 8" apart · Rows 10" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| 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 | — |
| 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: too_alkaline
🗺️ USDA Zone
Zone 4b
📆 Growing Season
83 days in Jackson County
Growing Tips for Ageratum in Jackson County
Direct sow Ageratum outdoors after June 13 in Jackson County when soil has warmed and frost danger has passed.
Your 83.0-day growing season in Jackson County is tight for Ageratum (60.0-75.0 days to maturity). Start indoors and choose early-maturing varieties.
Common pests for Ageratum in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
Jackson 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 →
Ageratum in Other Locations
Frequently Asked Questions
When should I plant Ageratum in Jackson County, CO?
Jackson County is in Zone 4b with an average last frost of June 13. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.
What planting zone is Jackson County, CO?
Jackson County, Colorado is in USDA Hardiness Zone 4b. The average last spring frost is June 13 and first fall frost is September 4.
When should I plant Ageratum in Jackson County County, ?
In Jackson County County, , plant Ageratum after the last frost (around June 13) and before the first frost (around September 4). Best results when soil holds above 50°F.
What growing zone is Jackson County County, for Ageratum?
Jackson County County sits in USDA Zone 4b. Ageratum grows reliably in zones 3a through 11b, so it's a good fit here.
Can Ageratum grow in Jackson County County's climate?
Yes — Ageratum grows well in Jackson County County's temperate climate. Jackson County County averages a 83-day frost-free season, with last frost around June 13 and first frost around September 4.
Your Jackson County Garden Planner — Free
A 22-page printable planner built for Jackson County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.