When to Plant Echinacea (Purple Coneflower) in Jefferson County, TN
What to do in June
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.
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Fire up the seed-starting tray: echinacea (purple coneflower)
Bottom-water once the first true leaves appear — it keeps stems dry and knocks back damping-off.
A few tasks this June that'll pay off in July
- First harvests: echinacea (purple coneflower)
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.
Jefferson County, Tennessee is in USDA Zone 7b. The average last spring frost is April 15 and the first fall frost is October 22, giving you a growing season of approximately 190 days.
At an elevation of 3,886 feet, Jefferson County receives approximately 44.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 93°F, providing good warmth for Echinacea (Purple Coneflower) during the growing season.
Jefferson County Soil Profile
Soil Type
Silt Loam
Soil pH
5.4-6.8
Drainage
Well Drained
Echinacea (Purple Coneflower) Planting Risk Windows
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 Jefferson County
How your county's soil matches Echinacea (Purple Coneflower)'s growing requirements.
Soil pH
Your soil pH (5.4–6.8) overlaps with Echinacea (Purple Coneflower)'s range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Jefferson County is excellent for Echinacea (Purple Coneflower) — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (3.2%). Annual compost additions will help Echinacea (Purple Coneflower).
How to Plant Echinacea (Purple Coneflower)
Succession Planting Echinacea (Purple Coneflower)
Sow every 8 weeks. Last sowing by Jul 24 to harvest before frost.
Echinacea (Purple Coneflower) Water Budget
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 | — | 3.4" | 0" | ❄️ Dormant |
| Feb | — | 3.8" | 0" | ❄️ Dormant |
| Mar | — | 4" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.4" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 4.5" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.7" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 2.8" | 0" | ✅ Rainfall sufficient |
| Nov | — | 3.6" | 0" | ❄️ Dormant |
| Dec | — | 3.9" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Jefferson 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) Planting Timeline — Jefferson County, TN
Echinacea (Purple Coneflower) Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 11 | Feb 11 – Feb 25 |
| Transplant Outdoors | April 22 | Apr 22 – May 6 |
| Direct Sow | April 22 | Apr 22 – May 13 |
| Bloom | July 8 | Jul 8 – Nov 11 |
Plant 0.3" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | — |
| April | Transplant Outdoors Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | Bloom |
| 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 7b
📆 Growing Season
190 days in Jefferson County
Growing Tips for Echinacea (Purple Coneflower) in Jefferson County
Direct sow Echinacea (Purple Coneflower) outdoors after April 15 in Jefferson County when soil has warmed and frost danger has passed.
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 →
Echinacea (Purple Coneflower) in Other Locations
Frequently Asked Questions
When should I plant Echinacea (Purple Coneflower) in Jefferson County, TN?
Jefferson County is in Zone 7b with an average last frost of April 15. Plan your Echinacea (Purple Coneflower) planting based on this frost date — see the calendar above for exact timing.
What planting zone is Jefferson County, TN?
Jefferson County, Tennessee is in USDA Hardiness Zone 7b. The average last spring frost is April 15 and first fall frost is October 22.
Your Jefferson County Garden Planner — Free
A 22-page printable planner built for Jefferson 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.