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When to plant Ageratum in Pope County County,

Aim to plant Ageratum in Pope County County on or after May 11; the window stays open through June 1. Pope County County's 152-day frost-free season gives you a single solid spring crop with a brief fall option.

When to Plant Ageratum in Pope County, MN

Pope County, Minnesota Zone 4b June

June in the garden — Pope County, Minnesota

Welcome to June in Zone 4b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost May 4
Avg. first frost October 3
Soil temp (4") 65°F
Watering Low
Pest pressure High
Daylight 15.5 hrs
  1. Begin indoor sowing: ageratum

    Your window is short. These crops want several weeks of indoor growth before they go outside.

A few tasks this June that'll pay off in July
  • 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.

Pope County, Minnesota is in USDA Zone 4b. The average last spring frost is May 4 and the first fall frost is October 3, giving you a growing season of approximately 152 days.

At an elevation of 1,061 feet, Pope County receives approximately 31.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Ageratum to ensure they mature before fall.

Annual Blooms in Multi-season Pollinator-friendly Good for cutting
Pope County, MN (Zone 4b) Moderate season
152 days
Last Spring Frost May 4
152 growing days
First Fall Frost October 3
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Pope County Soil Profile

Soil Type

Silt Loam

Soil pH

6-7

Drainage

Well Drained

Ageratum Planting Risk Windows

Early Start (70% safe) ✓ Fits season (12 days to spare)
Start indoors: Mar 9 Transplant: May 4 🌸 Bloom: Jun 29 – Sep 14
Recommended (50%) ✓ Fits season (12 days to spare)
Start indoors: Mar 16 Transplant: May 11 🌸 Bloom: Jul 6 – Sep 21
Safe Start (90%) ✓ Fits season (10 days to spare)
Start indoors: Mar 29 Transplant: May 24 🌸 Bloom: Jul 19 – Oct 4

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 Pope County

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

Soil pH

Your soil pH (6.0–7.0) is within Ageratum's preferred range (6.0–7.0).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.6%) — Ageratum will thrive.

How to Plant Ageratum

8"
Between Plants
10"
Between Rows

Succession Planting Ageratum

2
successive plantings in your 152-day season

Sow every 6.9 weeks. Last sowing by Jul 20 to harvest before frost.

Ageratum Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 228 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 2" 0" ❄️ Dormant
Apr 3.4" 0" ❄️ Dormant
May 4.3" 4" 0.3" 💧 Light watering
Jun 4.3" 3.9" 0.4" 💧 Light watering
Jul 4.3" 3.1" 1.2" 💧 Light watering
Aug 4.3" 3.4" 0.9" 💧 Light watering
Sep 4.3" 2.7" 1.6" 💧 Light watering
Oct 4.3" 2.3" 2" 💧 Light watering
Nov 2" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Pope 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 ~878 GDD — county provides 1,976 GDD Excellent fit

Ageratum Planting Timeline — Pope County, MN

Ageratum Planting Calendar

Activity When Date Range
Start Indoors March 16 Mar 16 – Mar 30
Transplant Outdoors May 11 May 11 – May 25
Direct Sow May 11 May 11 – Jun 1
Bloom July 6 Jul 6 – Sep 21

· 8" apart · Rows 10" apart

Month-by-Month Timeline

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

🗺️ USDA Zone

Zone 4b

📆 Growing Season

152 days in Pope County

Growing Tips for Ageratum in Pope County

Direct sow Ageratum outdoors after May 04 in Pope 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 Pope County, MN?

Pope County is in Zone 4b with an average last frost of May 4. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.

What planting zone is Pope County, MN?

Pope County, Minnesota is in USDA Hardiness Zone 4b. The average last spring frost is May 4 and first fall frost is October 3.

When should I plant Ageratum in Pope County, ?

In Pope County, , plant Ageratum after the last frost (around May 4) and before the first frost (around October 3). Best results when soil holds above 50°F.

What growing zone is Pope County, for Ageratum?

Pope 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 Pope County's climate?

Yes — Ageratum grows well in Pope County's temperate climate. Pope County averages a 152-day frost-free season, with last frost around May 4 and first frost around October 3.

🌱

Your Pope County Garden Planner — Free

A 22-page printable planner built for Pope 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.

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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 Pope County, MN. Local conditions may vary. Last updated: June 2026.

Sources & credits

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