When to plant Phlox in Edwards County County,
In Zone 6b (Edwards County County), direct-sow Phlox between April 16 and May 7 for spring, after the April 9 last-frost mark.
When to Plant Phlox in Edwards County, IL
Your June game plan for Edwards County, Illinois
Welcome to June in Zone 6b. These are the moves that will have the biggest impact on your growing season.
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Fire up the seed-starting tray: phlox
You're about 19 weeks out from your last frost — the perfect window to get these germinating indoors.
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Basket week: phlox
If you can't use it all right away, check the food-preservation section of your planner.
Get ahead of July
- First harvests: phlox
Garden Phlox (Phlox paniculata) is a beloved native perennial of eastern North America, producing large, domed clusters of fragrant flowers atop upright stems from mid-summer into fall. Its sweet honey-like fragrance carries on summer evenings and draws hummingbirds, butterflies, and sphinx moths. Modern cultivars offer colors spanning white, pink, salmon, red, purple, and bicolors. A classic cottage garden stalwart, phlox combines well with black-eyed Susans, echinacea, and ornamental grasses in naturalistic plantings. Select mildew-resistant cultivars for best long-term performance.
Edwards County, Illinois is in USDA Zone 6b. The average last spring frost is April 9 and the first fall frost is October 28, giving you a growing season of approximately 202 days.
At an elevation of 1,374 feet, Edwards County receives approximately 35.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Phlox during the growing season.
Edwards County Soil Profile
Soil Type
Silt Loam
Soil pH
6-7.2
Drainage
Well Drained
Phlox 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 Edwards County
How your county's soil matches Phlox's growing requirements.
Soil pH
Your soil pH (6.0–7.2) overlaps with Phlox's range (6.0–7.0), though not a perfect match.
Soil Texture
The silt loam soil in Edwards County is excellent for Phlox — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.7%) — Phlox will thrive.
How to Plant Phlox
Succession Planting Phlox
Sow every 9.1 weeks. Last sowing by Jul 10 to harvest before frost.
Phlox Water Budget
Monthly Watering Guide for Phlox
Phlox needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Phlox Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.5" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| May | 4.3" | 4" | 0.3" | 💧 Light watering |
| Jun | 4.3" | 5" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 3.9" | 0.4" | 💧 Light watering |
| Aug | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Sep | 4.3" | 3.1" | 1.2" | 💧 Light watering |
| Oct | 4.3" | 2.9" | 1.4" | 💧 Light watering |
| Nov | — | 2.3" | 0" | ❄️ Dormant |
| Dec | — | 2.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Edwards County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Phlox 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.
Phlox Planting Timeline — Edwards County, IL
Phlox Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 5 | Feb 5 – Feb 19 |
| Transplant Outdoors | April 16 | Apr 16 – Apr 30 |
| Direct Sow | April 16 | Apr 16 – May 7 |
| Bloom | June 25 | Jun 25 – Sep 17 |
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 | Direct Sow |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
80–110 days
🧪 Soil pH
Needs 6–7 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
202 days in Edwards County
Growing Tips for Phlox in Edwards County
Direct sow Phlox outdoors after April 09 in Edwards County when soil has warmed and frost danger has passed.
General growing tips
Start seeds indoors 8–10 weeks before last frost, or transplant container divisions in spring. Named cultivar seeds may not come true; divisions from named plants are the preferred propagation method. Space generously (18–24 inches) and avoid overhead watering to reduce powdery mildew risk. Good air circulation is critical — thin clumps to the strongest 5–7 stems per plant in spring. Deadhead after the primary bloom flush to encourage secondary flowering. Division every 2–3 years in spring keeps plants vigorous. Fall planting of divisions (Zones 5+) is equally effective. Year 2+ plants develop into full clumps with the most prolific bloom.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Phlox in Other Locations
Frequently Asked Questions
When should I plant Phlox in Edwards County, IL?
Edwards County is in Zone 6b with an average last frost of April 9. Plan your Phlox planting based on this frost date — see the calendar above for exact timing.
What planting zone is Edwards County, IL?
Edwards County, Illinois is in USDA Hardiness Zone 6b. The average last spring frost is April 9 and first fall frost is October 28.
When should I plant Phlox in Edwards County County, ?
In Edwards County County, , plant Phlox after the last frost (around April 9) and before the first frost (around October 28). Best results when soil holds above 50°F.
What growing zone is Edwards County County, for Phlox?
Edwards County County sits in USDA Zone 6b. Phlox grows reliably in zones 3a through 9a, so it's a good fit here.
Can Phlox grow in Edwards County County's climate?
Yes — Phlox grows well in Edwards County County's temperate climate. Edwards County County averages a 202-day frost-free season, with last frost around April 9 and first frost around October 28.
Your Edwards County Garden Planner — Free
A 22-page printable planner built for Edwards County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.