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When to plant Phlox in Cleburne County, AR

In Zone 7b (Cleburne County), direct-sow Phlox between April 4 and April 25 for spring, after the March 28 last-frost mark.

When to Plant Phlox in Cleburne County, AR

Cleburne County, Arkansas Zone 7b June

Your June planting checklist for Cleburne County, Arkansas

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

Avg. last frost March 28
Avg. first frost November 2
Soil temp (4") 79°F
Watering Low
Pest pressure High
Daylight 14.4 hrs
  1. Collect phlox at their peak

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

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  • First harvests: phlox

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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.

Cleburne County, Arkansas is in USDA Zone 7b. The average last spring frost is March 28 and the first fall frost is November 2, giving you a growing season of approximately 219 days.

At an elevation of 1,207 feet, Cleburne County receives approximately 48.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Phlox during the growing season.

Perennial Blooms in Summer Pollinator-friendly Good for cutting Fragrant
Cleburne County, AR (Zone 7b) Long season
219 days
Last Spring Frost March 28
219 growing days
First Fall Frost November 2

Cleburne County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-6.7

Drainage

Well Drained

Phlox Planting Risk Windows

Early Start (70% safe) ✓ Fits season (60 days to spare)
Start indoors: Jan 16 Transplant: Mar 27 🌸 Bloom: Jun 5 – Aug 28
Recommended (50%) ✓ Fits season (58 days to spare)
Start indoors: Jan 24 Transplant: Apr 4 🌸 Bloom: Jun 13 – Sep 5
Safe Start (90%) ✓ Fits season (60 days to spare)
Start indoors: Feb 14 Transplant: Apr 25 🌸 Bloom: Jul 4 – Sep 26

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 Cleburne County

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

Soil pH

Your soil pH (5.4–6.7) overlaps with Phlox's range (6.0–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Cleburne County is excellent for Phlox — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.7%). Annual compost additions will help Phlox.

How to Plant Phlox

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

Succession Planting Phlox

3
successive plantings in your 219-day season

Sow every 9.1 weeks. Last sowing by Jul 15 to harvest before frost.

Phlox Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 132 gal / 100 sq ft

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 3.9" 0" ❄️ Dormant
Feb 3.6" 0" ❄️ Dormant
Mar 4.3" 4.4" 0" ✅ Rainfall sufficient
Apr 4.3" 3.9" 0.4" 💧 Light watering
May 4.3" 3.5" 0.8" 💧 Light watering
Jun 4.3" 4.9" 0" ✅ Rainfall sufficient
Jul 4.3" 5.1" 0" ✅ Rainfall sufficient
Aug 4.3" 5.2" 0" ✅ Rainfall sufficient
Sep 4.3" 3.7" 0.6" 💧 Light watering
Oct 4.3" 3" 1.3" 💧 Light watering
Nov 4.3" 3.4" 0.9" 💧 Light watering
Dec 4" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Cleburne 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 needs ~1,734 GDD — county provides 3,996 GDD Excellent fit

Phlox Planting Timeline — Cleburne County, AR

Phlox Planting Calendar

Activity When Date Range
Start Indoors January 24 Jan 24 – Feb 7
Transplant Outdoors April 4 Apr 4 – Apr 18
Direct Sow April 4 Apr 4 – Apr 25
Bloom June 13 Jun 13 – Sep 5

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

Month-by-Month Timeline

MonthActivities
January Start Indoors
February Start Indoors
March
April Transplant Outdoors Direct Sow
May
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 7b

📆 Growing Season

219 days in Cleburne County

Growing Tips for Phlox in Cleburne County

Direct sow Phlox outdoors after March 28 in Cleburne 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 →

Frequently Asked Questions

When should I plant Phlox in Cleburne County, AR?

Cleburne County is in Zone 7b with an average last frost of March 28. Plan your Phlox planting based on this frost date — see the calendar above for exact timing.

What planting zone is Cleburne County, AR?

Cleburne County, Arkansas is in USDA Hardiness Zone 7b. The average last spring frost is March 28 and first fall frost is November 2.

When should I plant Phlox in Cleburne County, AR?

In Cleburne County, AR, plant Phlox after the last frost (around March 28) and before the first frost (around November 2). Best results when soil holds above 50°F.

What growing zone is Cleburne County, AR for Phlox?

Cleburne County sits in USDA Zone 7b. Phlox grows reliably in zones 3a through 9a, so it's a good fit here.

Can Phlox grow in Cleburne County's climate?

Yes — Phlox grows well in Cleburne County's temperate climate. Cleburne County averages a 219-day frost-free season, with last frost around March 28 and first frost around November 2.

🌱

Your Cleburne County Garden Planner — Free

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

Sources & credits

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