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When to plant Phlox in Bollinger County County,

In Zone 6b (Bollinger County County), direct-sow Phlox between April 15 and May 6 for spring, after the April 8 last-frost mark.

When to Plant Phlox in Bollinger County, MO

Bollinger County, Missouri Zone 6b June

June in the garden — Bollinger County, Missouri

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

Avg. last frost April 8
Avg. first frost October 27
Soil temp (4") 74°F
Watering Low
Pest pressure High
Daylight 14.6 hrs
  1. Time to start phlox inside

    Label every cell. You will absolutely forget which is which otherwise.

  2. Start harvesting phlox

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

Looking ahead to July
  • 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.

Bollinger County, Missouri is in USDA Zone 6b. The average last spring frost is April 8 and the first fall frost is October 27, giving you a growing season of approximately 202 days.

At an elevation of 1,095 feet, Bollinger County receives approximately 37.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Phlox during the growing season.

Perennial Blooms in Summer Pollinator-friendly Good for cutting Fragrant
Bollinger County, MO (Zone 6b) Long season
202 days
Last Spring Frost April 8
202 growing days
First Fall Frost October 27
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Bollinger County Soil Profile

Soil Type

Silt Loam

Soil pH

5.4-7.1

Drainage

Well Drained

Phlox Planting Risk Windows

Early Start (70% safe) ✓ Fits season (40 days to spare)
Start indoors: Jan 29 Transplant: Apr 9 🌸 Bloom: Jun 18 – Sep 10
Recommended (50%) ✓ Fits season (41 days to spare)
Start indoors: Feb 4 Transplant: Apr 15 🌸 Bloom: Jun 24 – Sep 16
Safe Start (90%) ✓ Fits season (43 days to spare)
Start indoors: Feb 19 Transplant: Apr 30 🌸 Bloom: Jul 9 – Oct 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 Bollinger County

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

Soil pH

Your soil pH (5.4–7.1) overlaps with Phlox's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Phlox.

Organic Matter

Organic matter is moderate (2.8%). Annual compost additions will help Phlox.

How to Plant Phlox

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

Succession Planting Phlox

2
successive plantings in your 202-day season

Sow every 9.1 weeks. Last sowing by Jul 09 to harvest before frost.

Phlox Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 1.5" 0" ❄️ Dormant
Feb 1.8" 0" ❄️ Dormant
Mar 2.9" 0" ❄️ Dormant
Apr 4.3" 4.1" 0.2" 💧 Light watering
May 4.3" 4" 0.3" 💧 Light watering
Jun 4.3" 4.8" 0" ✅ Rainfall sufficient
Jul 4.3" 3.8" 0.5" 💧 Light watering
Aug 4.3" 4.2" 0.1" 💧 Light watering
Sep 4.3" 3" 1.3" 💧 Light watering
Oct 4.3" 3.1" 1.2" 💧 Light watering
Nov 2.4" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Bollinger 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 ~1,591 GDD — county provides 3,383 GDD Excellent fit

Phlox Planting Timeline — Bollinger County, MO

Phlox Planting Calendar

Activity When Date Range
Start Indoors February 4 Feb 4 – Feb 18
Transplant Outdoors April 15 Apr 15 – Apr 29
Direct Sow April 15 Apr 15 – May 6
Bloom June 24 Jun 24 – Sep 16

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

80–110 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

202 days in Bollinger County

Growing Tips for Phlox in Bollinger County

Direct sow Phlox outdoors after April 08 in Bollinger 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 Bollinger County, MO?

Bollinger County is in Zone 6b with an average last frost of April 8. Plan your Phlox planting based on this frost date — see the calendar above for exact timing.

What planting zone is Bollinger County, MO?

Bollinger County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 8 and first fall frost is October 27.

When should I plant Phlox in Bollinger County County, ?

In Bollinger County County, , plant Phlox after the last frost (around April 8) and before the first frost (around October 27). Best results when soil holds above 50°F.

What growing zone is Bollinger County County, for Phlox?

Bollinger 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 Bollinger County County's climate?

Yes — Phlox grows well in Bollinger County County's temperate climate. Bollinger County County averages a 202-day frost-free season, with last frost around April 8 and first frost around October 27.

🌱

Your Bollinger County Garden Planner — Free

A 22-page printable planner built for Bollinger 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.

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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 Bollinger County, MO. 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.