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When to Plant Ageratum in Hall County, TX

Hall County, Texas Zone 7b June

Your June game plan for Hall County, Texas

Your garden in Hall County, Texas is working on a schedule, even when you're not. Here's where you should be this June.

Avg. last frost March 31
Avg. first frost November 6
Soil temp (4") 78°F
Watering High
Pest pressure High
Daylight 14.3 hrs
  1. It's harvest week for ageratum

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

Get ahead of 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.

Hall County, Texas is in USDA Zone 7b. The average last spring frost is March 31 and the first fall frost is November 6, giving you a growing season of approximately 220 days.

At an elevation of 1,213 feet, Hall County receives approximately 52.7 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 94°F, providing good warmth for Ageratum during the growing season. Sandy soil warms quickly in spring — great for early planting — but Ageratum will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Ageratum root diseases.

Annual Blooms in Multi-season Pollinator-friendly Good for cutting
Hall County, TX (Zone 7b) Long season
220 days
Last Spring Frost March 31
220 growing days
First Fall Frost November 6

Hall County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.4-8.8

Drainage

Well Drained

Ageratum Planting Risk Windows

Early Start (70% safe) ✓ Fits season (40 days to spare)
Start indoors: Feb 9 Transplant: Mar 23 🌸 Bloom: May 18 – Sep 21
Recommended (50%) ✓ Fits season (38 days to spare)
Start indoors: Feb 17 Transplant: Mar 31 🌸 Bloom: May 26 – Sep 29
Safe Start (90%) ✓ Fits season (38 days to spare)
Start indoors: Mar 4 Transplant: Apr 15 🌸 Bloom: Jun 10 – Oct 14

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 Hall County

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

Soil pH

Your soil pH (7.4–8.8) is more alkaline than Ageratum prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Hall County warms quickly in spring but drains fast. Ageratum will need more frequent watering and regular compost additions to retain nutrients.

Organic Matter

Organic matter is low (0.9%). Add 2-3 inches of compost before planting Ageratum.

How to Plant Ageratum

8"
Between Plants
10"
Between Rows

Succession Planting Ageratum

4
successive plantings in your 220-day season

Sow every 6.9 weeks. Last sowing by Aug 23 to harvest before frost.

Ageratum Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — 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 3.5" 0" ❄️ Dormant
Feb 3.1" 0" ❄️ Dormant
Mar 4.3" 3.1" 1.2" 💧 Light watering
Apr 4.3" 1.8" 2.5" 🚿 Regular watering
May 4.3" 1.1" 3.2" 🚿 Regular watering
Jun 4.3" 2" 2.3" 🚿 Regular watering
Jul 4.3" 8.9" 0" ✅ Rainfall sufficient
Aug 4.3" 10" 0" ✅ Rainfall sufficient
Sep 4.3" 7.1" 0" ✅ Rainfall sufficient
Oct 4.3" 5.4" 0" ✅ Rainfall sufficient
Nov 4.3" 2.7" 1.6" 💧 Light watering
Dec 4" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Hall 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 ~1,384 GDD — county provides 4,510 GDD Excellent fit

Ageratum Planting Timeline — Hall County, TX

Ageratum Planting Calendar

Activity When Date Range
Start Indoors February 17 Feb 17 – Mar 3
Transplant Outdoors March 31 Mar 31 – Apr 14
Direct Sow March 31 Mar 31 – Apr 21
Bloom May 26 May 26 – Sep 29

· 8" apart · Rows 10" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors Transplant Outdoors Direct Sow
April Transplant Outdoors Direct Sow
May Bloom
June Bloom
July Bloom
August Bloom
September Bloom
October
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 7b

📆 Growing Season

220 days in Hall County

Growing Tips for Ageratum in Hall County

Direct sow Ageratum outdoors after March 31 in Hall County when soil has warmed and frost danger has passed.

Sandy soil in Hall County dries quickly — mulch Ageratum with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

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 Hall County, TX?

Hall County is in Zone 7b with an average last frost of March 31. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.

What planting zone is Hall County, TX?

Hall County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 31 and first fall frost is November 6.

🌱

Your Hall County Garden Planner — Free

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

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.