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When to plant Petunia in Hancock County County,

Hancock County County sits in cold Zone 6a. Plant Petunia April 21–May 5 for the single annual harvest; the October 18 first frost closes the window.

When to Plant Petunia in Hancock County, IL

Hancock County, Illinois Zone 6a June

Your June game plan for Hancock County, Illinois

A quick June briefing for Hancock County, Illinois gardeners — what's urgent, what's next, and what can wait.

Avg. last frost April 14
Avg. first frost October 18
Soil temp (4") 69°F
Watering Low
Pest pressure High
Daylight 14.9 hrs
  1. Time to start petunia inside

    These need a head start before your last frost (April 14). Sow into cells now so you're ready to transplant in a few weeks.

  2. Start harvesting petunia

    Morning harvests are best — cooler temperatures mean crisper produce and longer fridge life.

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

Hancock County, Illinois is in USDA Zone 6a. The average last spring frost is April 14 and the first fall frost is October 18, giving you a growing season of approximately 187 days.

At an elevation of 758 feet, Hancock County receives approximately 37.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Petunia during the growing season.

Annual Blooms in Summer Pollinator-friendly Fragrant
Hancock County, IL (Zone 6a) Moderate season
187 days
Last Spring Frost April 14
187 growing days
First Fall Frost October 18

Hancock County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.8

Drainage

Well Drained

Petunia Planting Risk Windows

Early Start (70% safe) ✓ Fits season (11 days to spare)
Start indoors: Feb 12 Transplant: Apr 16 🌸 Bloom: Jun 25 – Oct 1
Recommended (50%) ✓ Fits season (12 days to spare)
Start indoors: Feb 17 Transplant: Apr 21 🌸 Bloom: Jun 30 – Oct 6
Safe Start (90%) ✓ Fits season (10 days to spare)
Start indoors: Mar 4 Transplant: May 6 🌸 Bloom: Jul 15 – 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 Hancock County

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

Soil pH

Your soil pH (5.9–6.8) overlaps with Petunia's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Petunia.

Organic Matter

Organic matter is excellent (4.9%) — Petunia will thrive.

How to Plant Petunia

12"
Between Plants
12"
Between Rows

Succession Planting Petunia

3
successive plantings in your 187-day season

Sow every 8 weeks. Last sowing by Jul 20 to harvest before frost.

Petunia Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 777 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 1.5" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 4.3" 3.1" 1.2" 💧 Light watering
May 4.3" 4.2" 0.1" 💧 Light watering
Jun 4.3" 4.4" 0" ✅ Rainfall sufficient
Jul 4.3" 4.6" 0" ✅ Rainfall sufficient
Aug 4.3" 4.2" 0.1" 💧 Light watering
Sep 4.3" 3.3" 1" 💧 Light watering
Oct 4.3" 3.1" 1.2" 💧 Light watering
Nov 2.7" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Hancock 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 ~1,220 GDD — county provides 2,851 GDD Excellent fit

Petunia Planting Timeline — Hancock County, IL

Petunia Planting Calendar

Activity When Date Range
Start Indoors February 17 Feb 17 – Mar 3
Transplant Outdoors April 21 Apr 21 – May 5
Bloom June 30 Jun 30 – Oct 6

· 12" apart · Rows 12" apart

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March Start Indoors
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 6a

📆 Growing Season

187 days in Hancock County

Growing Tips for Petunia in Hancock County

Direct sow Petunia outdoors after April 14 in Hancock 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 Hancock County, IL?

Hancock County is in Zone 6a with an average last frost of April 14. Plan your Petunia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Hancock County, IL?

Hancock County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 14 and first fall frost is October 18.

When should I plant Petunia in Hancock County, ?

In Hancock County, , plant Petunia after the last frost (around April 14) and before the first frost (around October 18). Best results when soil holds above 50°F.

What growing zone is Hancock County, for Petunia?

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

Can Petunia grow in Hancock County's climate?

Yes — Petunia grows well in Hancock County's temperate climate. Hancock County averages a 187-day frost-free season, with last frost around April 14 and first frost around October 18.

🌱

Your Hancock County Garden Planner — Free

A 22-page printable planner built for Hancock 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 Hancock County, IL. 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.