When to plant Ageratum in Cass County, MO
The best window to plant Ageratum in Cass County, is April 14–May 5, when soil warms to 50°F. Last frost typically hits April 14; first frost October 22.
When to Plant Ageratum in Cass County, MO
Your June planting checklist for Cass County, Missouri
If you only do a handful of things in the garden this June, make it these. They're sequenced around your zone's frost timing.
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Start ageratum under lights
Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.
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Basket week: ageratum
The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.
Get ahead of July
- First harvests: ageratum
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.
Cass County, Missouri is in USDA Zone 6b. The average last spring frost is April 14 and the first fall frost is October 22, giving you a growing season of approximately 191 days.
At an elevation of 910 feet, Cass County receives approximately 37 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Ageratum during the growing season.
Cass County Soil Profile
Soil Type
Silt Loam
Soil pH
5.7-6.8
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 Cass County
How your county's soil matches Ageratum's growing requirements.
Soil pH
Your soil pH (5.7–6.8) overlaps with Ageratum's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Cass County is excellent for Ageratum — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.9%). Annual compost additions will help Ageratum.
How to Plant Ageratum
Succession Planting Ageratum
Sow every 6.9 weeks. Last sowing by Aug 08 to harvest before frost.
Ageratum Water Budget
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 | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 2.4" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| May | 4.3" | 4.3" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 5.2" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Aug | 4.3" | 3.8" | 0.5" | 💧 Light watering |
| Sep | 4.3" | 3.3" | 1" | 💧 Light watering |
| Oct | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| Nov | — | 2.8" | 0" | ❄️ Dormant |
| Dec | — | 1.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Cass 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 — Cass County, MO
Ageratum Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 24 | Feb 24 – Mar 10 |
| Transplant Outdoors | April 14 | Apr 14 – Apr 28 |
| Direct Sow | April 14 | Apr 14 – May 5 |
| Bloom | June 9 | Jun 9 – Sep 22 |
· 8" apart · Rows 10" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | Direct Sow |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
60–75 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
191 days in Cass County
Growing Tips for Ageratum in Cass County
Direct sow Ageratum outdoors after April 14 in Cass 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 →
Ageratum in Other Locations
Frequently Asked Questions
When should I plant Ageratum in Cass County, MO?
Cass County is in Zone 6b with an average last frost of April 14. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.
What planting zone is Cass County, MO?
Cass County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 14 and first fall frost is October 22.
When should I plant Ageratum in Cass County, MO?
In Cass County, MO, plant Ageratum after the last frost (around April 14) and before the first frost (around October 22). Best results when soil holds above 50°F.
What growing zone is Cass County, MO for Ageratum?
Cass County sits in USDA Zone 6b. Ageratum grows reliably in zones 3a through 11b, so it's a good fit here.
Can Ageratum grow in Cass County's climate?
Yes — Ageratum grows well in Cass County's temperate climate. Cass County averages a 191-day frost-free season, with last frost around April 14 and first frost around October 22.
Your Cass County Garden Planner — Free
A 22-page printable planner built for Cass County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.