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When to plant Petunia in Dent County, MO

Plant Petunia in Dent County during the brief April 17–May 1 window. With 200 frost-free days, fall plantings can't mature before October 27.

When to Plant Petunia in Dent County, MO

Dent County, Missouri Zone 6b June

Your June gardening checklist

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

Avg. last frost April 10
Avg. first frost October 27
Soil temp (4") 74°F
Watering Low
Pest pressure High
Daylight 14.6 hrs
  1. Time to start petunia inside

    A seed-starting mix and a sunny window (or a grow light) are all you need. Keep soil warm — around 70°F — for fast germination.

  2. Pick petunia

    Check every 1–2 days. Many of these get tough or go to seed if you wait too long.

A few tasks this June that'll pay off in July
  • First harvests: petunia

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Petunias (Petunia x hybrida) are warm-season tender annuals prized for their prolific, trumpet-shaped blooms in nearly every color. They perform from hanging baskets to garden borders and bloom continuously from late spring until frost, provided spent flowers are removed regularly.

Dent County, Missouri is in USDA Zone 6b. The average last spring frost is April 10 and the first fall frost is October 27, giving you a growing season of approximately 200 days.

At an elevation of 774 feet, Dent County receives approximately 31.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Petunia during the growing season.

Annual Blooms in Summer Pollinator-friendly Fragrant
Dent County, MO (Zone 6b) Long season
200 days
Last Spring Frost April 10
200 growing days
First Fall Frost October 27

Dent County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.7

Drainage

Well Drained

Petunia Planting Risk Windows

Early Start (70% safe) ✓ Fits season (14 days to spare)
Start indoors: Feb 7 Transplant: Apr 11 🌸 Bloom: Jun 20 – Oct 3
Recommended (50%) ✓ Fits season (18 days to spare)
Start indoors: Feb 13 Transplant: Apr 17 🌸 Bloom: Jun 26 – Oct 9
Safe Start (90%) ✓ Fits season (20 days to spare)
Start indoors: Feb 26 Transplant: Apr 30 🌸 Bloom: Jul 9 – Oct 22

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 Dent County

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

Soil pH

Your soil pH (5.5–6.7) overlaps with Petunia's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.6%). Annual compost additions will help Petunia.

How to Plant Petunia

12"
Between Plants
12"
Between Rows

Succession Planting Petunia

3
successive plantings in your 200-day season

Sow every 8 weeks. Last sowing by Jul 29 to harvest before frost.

Petunia Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 595 gal / 100 sq ft

Monthly Watering Guide for Petunia

Petunia needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Petunia Needs Rainfall You Supplement Action
Jan 1.3" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2.4" 0" ❄️ Dormant
Apr 4.3" 2.8" 1.5" 💧 Light watering
May 4.3" 3.7" 0.6" 💧 Light watering
Jun 4.3" 4" 0.3" 💧 Light watering
Jul 4.3" 3.7" 0.6" 💧 Light watering
Aug 4.3" 3.5" 0.8" 💧 Light watering
Sep 4.3" 2.4" 1.9" 💧 Light watering
Oct 4.3" 2.2" 2.1" 💧 Light watering
Nov 2.4" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Dent County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Petunia 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.

Petunia needs ~1,460 GDD — county provides 3,650 GDD Excellent fit

Petunia Planting Timeline — Dent County, MO

Petunia Planting Calendar

Activity When Date Range
Start Indoors February 13 Feb 13 – Feb 27
Transplant Outdoors April 17 Apr 17 – May 1
Bloom June 26 Jun 26 – Oct 9

· 12" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

200 days in Dent County

Growing Tips for Petunia in Dent County

Direct sow Petunia outdoors after April 10 in Dent County when soil has warmed and frost danger has passed.

Common pests for Petunia in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

Start seeds indoors 8–10 weeks before last frost; seeds need light to germinate — press onto moist mix surface, do not cover. Transplant after last frost once nights stay above 50°F. Pinch back leggy plants mid-summer to encourage bushy re-bloom. Wave/spreading types tolerate light shade but bloom less. Feed every 2 weeks with balanced fertilizer once established.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Petunia in Dent County, MO?

Dent County is in Zone 6b with an average last frost of April 10. Plan your Petunia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Dent County, MO?

Dent County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 10 and first fall frost is October 27.

When should I plant Petunia in Dent County, MO?

In Dent County, MO, plant Petunia after the last frost (around April 10) and before the first frost (around October 27). Best results when soil holds above 50°F.

What growing zone is Dent County, MO for Petunia?

Dent County sits in USDA Zone 6b. Petunia grows reliably in zones 2a through 11b, so it's a good fit here.

Can Petunia grow in Dent County's climate?

Yes — Petunia grows well in Dent County's temperate climate. Dent County averages a 200-day frost-free season, with last frost around April 10 and first frost around October 27.

🌱

Your Dent County Garden Planner — Free

A 22-page printable planner built for Dent 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 Dent 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.