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When to Plant Phlox in Clearfield County, PA

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.

Clearfield County, Pennsylvania is in USDA Zone 6a. The average last spring frost is May 2 and the first fall frost is October 18, giving you a growing season of approximately 169 days.

At an elevation of 69 feet, Clearfield County receives approximately 47 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Phlox to ensure they mature before fall.

Perennial Blooms in Summer Pollinator-friendly Good for cutting Fragrant
Clearfield County, PA (Zone 6a) Moderate season
169 days
Last Spring Frost May 2
169 growing days
First Fall Frost October 18

Clearfield County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Phlox Planting Timeline — Clearfield County, PA

Phlox Planting Calendar

Activity When Date Range
Start Indoors February 28 Feb 28 – Mar 14
Transplant Outdoors May 9 May 9 – May 23
Direct Sow May 9 May 9 – May 30
Bloom July 18 Jul 18 – Oct 10

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

80–110 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 6a

📆 Growing Season

169 days in Clearfield County

Growing Tips for Clearfield County

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 Clearfield County, PA?

Clearfield County is in Zone 6a with an average last frost of May 2. Plan your Phlox planting based on this frost date — see the calendar above for exact timing.

What planting zone is Clearfield County, PA?

Clearfield County, Pennsylvania is in USDA Hardiness Zone 6a. The average last spring frost is May 2 and first fall frost is October 18.

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A 22-page printable planner built for Clearfield County (Zone 6a). 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 Clearfield County, PA. Local conditions may vary. Last updated: June 2026.

Sources & credits

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