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When to Plant Ageratum in Briscoe County, TX

Briscoe County, Texas Zone 7b June

June in the garden — Briscoe County, Texas

June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Briscoe County, Texas.

Avg. last frost April 6
Avg. first frost November 2
Soil temp (4") 68°F
Watering High
Pest pressure High
Daylight 14.3 hrs
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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.

Briscoe County, Texas is in USDA Zone 7b. The average last spring frost is April 6 and the first fall frost is November 2, giving you a growing season of approximately 210 days.

At an elevation of 4,513 feet, Briscoe County receives approximately 47.4 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 98°F, so Ageratum may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Ageratum will need more frequent watering and organic matter to retain nutrients.

Annual Blooms in Multi-season Pollinator-friendly Good for cutting
Briscoe County, TX (Zone 7b) Long season
210 days
Last Spring Frost April 6
210 growing days
First Fall Frost November 2
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Briscoe County Soil Profile

Soil Type

Sandy Loam

Soil pH

7.4-8.3

Drainage

Well Drained

Ageratum Planting Risk Windows

Early Start (70% safe) ✓ Fits season (33 days to spare)
Start indoors: Feb 12 Transplant: Mar 26 🌸 Bloom: May 21 – Sep 24
Recommended (50%) ✓ Fits season (28 days to spare)
Start indoors: Feb 23 Transplant: Apr 6 🌸 Bloom: Jun 1 – Oct 5
Safe Start (90%) ✓ Fits season (35 days to spare)
Start indoors: Mar 5 Transplant: Apr 16 🌸 Bloom: Jun 11 – Oct 15

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 Briscoe County

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

Soil pH

Your soil pH (7.4–8.3) is more alkaline than Ageratum prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Sandy soil in Briscoe 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 (1.0%). 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 210-day season

Sow every 6.9 weeks. Last sowing by Aug 19 to harvest before frost.

Ageratum Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 117 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 3.2" 0" ❄️ Dormant
Feb 3" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 4.3" 1.6" 2.7" 🚿 Regular watering
May 4.3" 1" 3.3" 🚿 Regular watering
Jun 4.3" 1.9" 2.4" 🚿 Regular watering
Jul 4.3" 7.5" 0" ✅ Rainfall sufficient
Aug 4.3" 10.4" 0" ✅ Rainfall sufficient
Sep 4.3" 6.2" 0" ✅ Rainfall sufficient
Oct 4.3" 4.1" 0.2" 💧 Light watering
Nov 4.3" 3" 1.3" 💧 Light watering
Dec 2.9" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Nov in Briscoe 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 ~1,586 GDD — county provides 4,935 GDD Excellent fit

Ageratum Planting Timeline — Briscoe County, TX

Ageratum Planting Calendar

Activity When Date Range
Start Indoors February 23 Feb 23 – Mar 9
Transplant Outdoors April 6 Apr 6 – Apr 20
Direct Sow April 6 Apr 6 – Apr 27
Bloom June 1 Jun 1 – Oct 5

· 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 Bloom
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: too_alkaline

🗺️ USDA Zone

Zone 7b

📆 Growing Season

210 days in Briscoe County

Growing Tips for Ageratum in Briscoe County

Direct sow Ageratum outdoors after April 06 in Briscoe County when soil has warmed and frost danger has passed.

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

With summer highs reaching 98°F in Briscoe County, provide afternoon shade for Ageratum and water deeply in the morning.

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 Briscoe County, TX?

Briscoe County is in Zone 7b with an average last frost of April 6. Plan your Ageratum planting based on this frost date — see the calendar above for exact timing.

What planting zone is Briscoe County, TX?

Briscoe County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is April 6 and first fall frost is November 2.

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A 22-page printable planner built for Briscoe 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 Briscoe County, TX. Local conditions may vary. Last updated: June 2026.

Sources & credits

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