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When to plant Ageratum in Jasper County, MO

Jasper County sits in USDA Zone 7a. Plant Ageratum between April 9 (after last frost on April 9) and April 30.

When to Plant Ageratum in Jasper County, MO

Jasper County, Missouri Zone 7a June

Your June gardening checklist

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.

Avg. last frost April 9
Avg. first frost October 26
Soil temp (4") 75°F
Watering Low
Pest pressure High
Daylight 14.5 hrs
  1. Basket week: ageratum

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

Before July arrives, get these ready
  • 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.

Jasper County, Missouri is in USDA Zone 7a. The average last spring frost is April 9 and the first fall frost is October 26, giving you a growing season of approximately 200 days.

At an elevation of 1,156 feet, Jasper County receives approximately 30.8 inches of rainfall annually with predominantly silt 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
Jasper County, MO (Zone 7a) Long season
200 days
Last Spring Frost April 9
200 growing days
First Fall Frost October 26

Jasper County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.6

Drainage

Well Drained

Ageratum Planting Risk Windows

Early Start (70% safe) ✓ Fits season (32 days to spare)
Start indoors: Feb 20 Transplant: Apr 3 🌸 Bloom: May 29 – Sep 18
Recommended (50%) ✓ Fits season (32 days to spare)
Start indoors: Feb 26 Transplant: Apr 9 🌸 Bloom: Jun 4 – Sep 24
Safe Start (90%) ✓ Fits season (34 days to spare)
Start indoors: Mar 10 Transplant: Apr 21 🌸 Bloom: Jun 16 – Oct 6

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 Jasper County

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

Soil pH

Your soil pH (5.5–6.6) overlaps with Ageratum's range (6.0–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Jasper County is excellent for Ageratum — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.8%). Annual compost additions will help Ageratum.

How to Plant Ageratum

8"
Between Plants
10"
Between Rows

Succession Planting Ageratum

3
successive plantings in your 200-day season

Sow every 6.9 weeks. Last sowing by Aug 12 to harvest before frost.

Ageratum Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 754 gal / 100 sq ft
Drought risk

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 1.3" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 1.8" 0" ❄️ Dormant
Apr 4.3" 2.9" 1.4" 💧 Light watering
May 4.3" 3.5" 0.8" 💧 Light watering
Jun 4.3" 4.3" 0" ✅ Rainfall sufficient
Jul 4.3" 3.1" 1.2" 💧 Light watering
Aug 4.3" 3.6" 0.7" 💧 Light watering
Sep 4.3" 2.5" 1.8" 💧 Light watering
Oct 4.3" 2.4" 1.9" 💧 Light watering
Nov 2.2" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Jasper 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 2,900 GDD Excellent fit

Ageratum Planting Timeline — Jasper County, MO

Ageratum Planting Calendar

Activity When Date Range
Start Indoors February 26 Feb 26 – Mar 12
Transplant Outdoors April 9 Apr 9 – Apr 23
Direct Sow April 9 Apr 9 – Apr 30
Bloom June 4 Jun 4 – Sep 24

· 8" apart · Rows 10" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

60–75 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

200 days in Jasper County

Growing Tips for Ageratum in Jasper County

Direct sow Ageratum outdoors after April 09 in Jasper 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 →

Frequently Asked Questions

When should I plant Ageratum in Jasper County, MO?

Jasper County is in Zone 7a with an average last frost of April 9. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jasper County, MO?

Jasper County, Missouri is in USDA Hardiness Zone 7a. The average last spring frost is April 9 and first fall frost is October 26.

When should I plant Ageratum in Jasper County, MO?

In Jasper County, MO, plant Ageratum after the last frost (around April 9) and before the first frost (around October 26). Best results when soil holds above 50°F.

What growing zone is Jasper County, MO for Ageratum?

Jasper County sits in USDA Zone 7a. Ageratum grows reliably in zones 3a through 11b, so it's a good fit here.

Can Ageratum grow in Jasper County's climate?

Yes — Ageratum grows well in Jasper County's temperate climate. Jasper County averages a 200-day frost-free season, with last frost around April 9 and first frost around October 26.

🌱

Your Jasper County Garden Planner — Free

A 22-page printable planner built for Jasper County (Zone 7a). 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 Jasper County, MO. Local conditions may vary. Last updated: June 2026.

Sources & credits

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