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When to plant Phlox in Greeley County, KS

Greeley County gardeners should plant Phlox between May 7 and May 28 in spring. With Greeley County's Zone 6a climate (last frost April 30), Phlox needs 80–110 days to mature — plant by June 22 for a full harvest.

When to Plant Phlox in Greeley County, KS

Greeley County, Kansas Zone 6a July

Greeley County, Kansas gardeners: here's your July plan

July is a pivotal month for Greeley County, Kansas gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost April 30
Avg. first frost October 10
Soil temp (4") 75°F
Watering High
Pest pressure High
Daylight 14.4 hrs
  1. Time to start phlox inside

    Your window is short. These crops want several weeks of indoor growth before they go outside.

  2. Collect phlox at their peak

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

August will be here before you know it — start on
  • 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.

Greeley County, Kansas is in USDA Zone 6a. The average last spring frost is April 30 and the first fall frost is October 10, giving you a growing season of approximately 163 days.

At an elevation of 963 feet, Greeley County receives approximately 21.1 inches of rainfall annually with predominantly loam soil. Summer highs average 87°F, providing good warmth for Phlox during the growing season.

Perennial Blooms in Summer Pollinator-friendly Good for cutting Fragrant
Greeley County, KS (Zone 6a) Moderate season
163 days
Last Spring Frost April 30
163 growing days
First Fall Frost October 10

Greeley County Soil Profile

Soil Type

Loam

Soil pH

6.2-7.2

Drainage

Well Drained

Phlox Planting Risk Windows

Early Start (70% safe) ✓ Fits season (2 days to spare)
Start indoors: Feb 22 Transplant: May 3 🌸 Bloom: Jul 12 – Oct 4
Recommended (50%) ✓ Fits season (2 days to spare)
Start indoors: Feb 26 Transplant: May 7 🌸 Bloom: Jul 16 – Oct 8
Safe Start (90%) ✓ Fits season (3 days to spare)
Start indoors: Mar 11 Transplant: May 20 🌸 Bloom: Jul 29 – Oct 21

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 Greeley County

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

Soil pH

Your soil pH (6.2–7.2) overlaps with Phlox's range (6.0–7.0), though not a perfect match.

Soil Texture

The loam soil in Greeley 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 (3.4%). 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 163-day season

Sow every 9.1 weeks. Last sowing by Jun 22 to harvest before frost.

Phlox Water Budget

Plant needs
1.0″/week
Rainfall provides
0.5″/week
You supply
0.9″/week
Watering frequency 2-3 times/week
Season total 1,317 gal / 100 sq ft
Drought risk

Water stress score is 8/10 — 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 1.4" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2.1" 0" ❄️ Dormant
Apr 4.3" 2" 2.3" 🚿 Regular watering
May 4.3" 2.7" 1.6" 💧 Light watering
Jun 4.3" 1.4" 2.9" 🚿 Regular watering
Jul 4.3" 1.6" 2.7" 🚿 Regular watering
Aug 4.3" 2" 2.3" 🚿 Regular watering
Sep 4.3" 2" 2.3" 🚿 Regular watering
Oct 4.3" 1.7" 2.6" 🚿 Regular watering
Nov 1.7" 0" ❄️ Dormant
Dec 1.1" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Greeley 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 ~1,449 GDD — county provides 2,485 GDD Excellent fit

Phlox Planting Timeline — Greeley County, KS

Phlox Planting Calendar

Activity When Date Range
Start Indoors February 26 Feb 26 – Mar 12
Transplant Outdoors May 7 May 7 – May 21
Direct Sow May 7 May 7 – May 28
Bloom July 16 Jul 16 – Oct 8

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

1"/week · 2-3 times/week

📅 Days to Maturity

80–110 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6a

📆 Growing Season

163 days in Greeley County

Growing Tips for Phlox in Greeley County

Direct sow Phlox outdoors after April 30 in Greeley County when soil has warmed and frost danger has passed.

Greeley County receives only 21" of rain annually. Phlox needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.

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 Greeley County, KS?

Greeley County is in Zone 6a with an average last frost of April 30. Plan your Phlox planting based on this frost date — see the calendar above for exact timing.

What planting zone is Greeley County, KS?

Greeley County, Kansas is in USDA Hardiness Zone 6a. The average last spring frost is April 30 and first fall frost is October 10.

When should I plant Phlox in Greeley County, KS?

In Greeley County, KS, plant Phlox after the last frost (around April 30) and before the first frost (around October 10). Best results when soil holds above 50°F.

What growing zone is Greeley County, KS for Phlox?

Greeley County sits in USDA Zone 6a. Phlox grows reliably in zones 3a through 9a, so it's a good fit here.

Can Phlox grow in Greeley County's climate?

Yes — Phlox grows well in Greeley County's temperate climate. Greeley County averages a 163-day frost-free season, with last frost around April 30 and first frost around October 10.

🌱

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A 22-page printable planner built for Greeley 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 Greeley County, KS. Local conditions may vary. Last updated: July 2026.

Sources & credits

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