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When to Plant Echinacea (Purple Coneflower) in Cass County, TX

Cass County, Texas Zone 8b June

This month in Cass County, Texas

Your Cass County, Texas garden is entering a new phase. Here's what's on the schedule for June and why each task matters now.

Avg. last frost March 14
Avg. first frost November 16
Soil temp (4") 84°F
Watering Low
Pest pressure High
Daylight 14.2 hrs
  1. It's harvest week for echinacea (purple coneflower)

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

Before July arrives, get these ready
  • First harvests: echinacea (purple coneflower)

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Echinacea purpurea (Purple Coneflower) is a long-lived native prairie perennial and one of the most valuable pollinator plants in North American gardens. Its distinctive daisy-like blooms — swept-back lavender-pink petals surrounding a spiny orange-brown cone — attract bees, butterflies, and goldfinches from summer into fall. Drought-tolerant once established, adaptable to average soils, and impressively long-lived; mature clumps bloom reliably for decades.

Cass County, Texas is in USDA Zone 8b. The average last spring frost is March 14 and the first fall frost is November 16, giving you a growing season of approximately 247 days.

At an elevation of 392 feet, Cass County receives approximately 71.7 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 94°F, providing good warmth for Echinacea (Purple Coneflower) during the growing season. Sandy soil warms quickly in spring — great for early planting — but Echinacea (Purple Coneflower) will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Echinacea (Purple Coneflower) root diseases.

Perennial Blooms in Summer Pollinator-friendly Deer-resistant Good for cutting
Cass County, TX (Zone 8b) Long season
247 days
Last Spring Frost March 14
247 growing days
First Fall Frost November 16

Cass County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.6-6.7

Drainage

Well Drained

Echinacea (Purple Coneflower) Planting Risk Windows

Early Start (70% safe) ✓ Fits season (38 days to spare)
Start indoors: Jan 9 Transplant: Mar 6 🌸 Bloom: May 15 – Oct 2
Recommended (50%) ✓ Fits season (37 days to spare)
Start indoors: Jan 17 Transplant: Mar 14 🌸 Bloom: May 23 – Oct 10
Safe Start (90%) ✓ Fits season (29 days to spare)
Start indoors: Feb 8 Transplant: Apr 5 🌸 Bloom: Jun 14 – Nov 1

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 Echinacea (Purple Coneflower)'s growing requirements.

Soil pH

Your soil pH (5.6–6.7) overlaps with Echinacea (Purple Coneflower)'s range (6.0–7.0), though not a perfect match.

Soil Texture

Sandy soil in Cass County warms quickly in spring but drains fast. Echinacea (Purple Coneflower) will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Echinacea (Purple Coneflower).

Organic Matter

Organic matter is low (1.9%). Add 2-3 inches of compost before planting Echinacea (Purple Coneflower).

How to Plant Echinacea (Purple Coneflower)

0.3"
Planting Depth
18"
Between Plants
24"
Between Rows

Succession Planting Echinacea (Purple Coneflower)

4
successive plantings in your 247-day season

Sow every 8 weeks. Last sowing by Aug 18 to harvest before frost.

Echinacea (Purple Coneflower) Water Budget

Plant needs
0.5″/week
Rainfall provides
1.2″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Echinacea (Purple Coneflower)

Echinacea (Purple Coneflower) needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Echinacea (Purple Coneflower) Needs Rainfall You Supplement Action
Jan 2" 0" ❄️ Dormant
Feb 2.5" 0" ❄️ Dormant
Mar 2.2" 4.3" 0" ✅ Rainfall sufficient
Apr 2.2" 6.6" 0" ✅ Rainfall sufficient
May 2.2" 11.3" 0" ✅ Rainfall sufficient
Jun 2.2" 12.4" 0" ✅ Rainfall sufficient
Jul 2.2" 8.9" 0" ✅ Rainfall sufficient
Aug 2.2" 8.7" 0" ✅ Rainfall sufficient
Sep 2.2" 6.7" 0" ✅ Rainfall sufficient
Oct 2.2" 4.3" 0" ✅ Rainfall sufficient
Nov 2.2" 2.4" 0" ✅ Rainfall sufficient
Dec 1.7" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Cass County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Echinacea (Purple Coneflower) 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.

Echinacea (Purple Coneflower) needs ~1,640 GDD — county provides 5,063 GDD Excellent fit

Echinacea (Purple Coneflower) Planting Timeline — Cass County, TX

Echinacea (Purple Coneflower) Planting Calendar

Activity When Date Range
Start Indoors January 17 Jan 17 – Jan 31
Transplant Outdoors March 14 Mar 14 – Mar 28
Direct Sow March 14 Mar 14 – Apr 4
Bloom May 23 May 23 – Oct 10

Plant 0.3" deep · 18" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 8b

📆 Growing Season

247 days in Cass County

Growing Tips for Echinacea (Purple Coneflower) in Cass County

Direct sow Echinacea (Purple Coneflower) outdoors after March 14 in Cass County when soil has warmed and frost danger has passed.

Sandy soil in Cass County dries quickly — mulch Echinacea (Purple Coneflower) with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

Common pests for Echinacea (Purple Coneflower) in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 8–10 weeks before last frost or direct-sow in fall for natural cold stratification. Seeds require 4–8 weeks of cold moist stratification (or fall sowing) for best germination. Transplant when night temps stay above 50°F. Full sun is essential for heavy bloom. Avoid over-fertilizing — lean soil produces more compact, floriferous plants. Deadhead for continuous bloom but leave some cones standing in fall for goldfinch seed harvest. Year 2+ plants bloom most heavily; first-year transplants may produce limited flowers. Divide congested clumps every 3–4 years in early spring.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Echinacea (Purple Coneflower) in Cass County, TX?

Cass County is in Zone 8b with an average last frost of March 14. Plan your Echinacea (Purple Coneflower) planting based on this frost date — see the calendar above for exact timing.

What planting zone is Cass County, TX?

Cass County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 14 and first fall frost is November 16.

🌱

Your Cass County Garden Planner — Free

A 22-page printable planner built for Cass County (Zone 8b). 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 Cass 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.