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When to plant Petunia in Ogle County County,

Plant Petunia in Ogle County County during the brief April 30–May 14 window. With 173 frost-free days, fall plantings can't mature before October 13.

When to Plant Petunia in Ogle County, IL

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.

Ogle County, Illinois is in USDA Zone 5b. The average last spring frost is April 23 and the first fall frost is October 13, giving you a growing season of approximately 173 days.

At an elevation of 890 feet, Ogle County receives approximately 39.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Petunia during the growing season.

Annual Blooms in Summer Pollinator-friendly Fragrant
Ogle County, IL (Zone 5b) Moderate season
173 days
Last Spring Frost April 23
173 growing days
First Fall Frost October 13
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Ogle County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.9

Drainage

Well Drained

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 1.9" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 4.3" 3.9" 0.4" 💧 Light watering
May 4.3" 4.1" 0.2" 💧 Light watering
Jun 4.3" 5" 0" ✅ Rainfall sufficient
Jul 4.3" 5" 0" ✅ Rainfall sufficient
Aug 4.3" 4" 0.3" 💧 Light watering
Sep 4.3" 3.9" 0.4" 💧 Light watering
Oct 4.3" 3.1" 1.2" 💧 Light watering
Nov 2.5" 0" ❄️ Dormant
Dec 2.3" 0" ❄️ Dormant

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

Petunia Planting Timeline — Ogle County, IL

Petunia Planting Calendar

Activity When Date Range
Start Indoors February 26 Feb 26 – Mar 12
Transplant Outdoors April 30 Apr 30 – May 14
Bloom July 9 Jul 9 – Oct 8

· 12" apart · Rows 12" apart

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5b

📆 Growing Season

173 days in Ogle County

Growing Tips for Ogle County

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 Ogle County, IL?

Ogle County is in Zone 5b with an average last frost of April 23. Plan your Petunia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Ogle County, IL?

Ogle County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 23 and first fall frost is October 13.

When should I plant Petunia in Ogle County County, ?

In Ogle County County, , plant Petunia after the last frost (around April 23) and before the first frost (around October 13). Best results when soil holds above 50°F.

What growing zone is Ogle County County, for Petunia?

Ogle County County sits in USDA Zone 5b. Petunia grows reliably in zones 2a through 11b, so it's a good fit here.

Can Petunia grow in Ogle County County's climate?

Yes — Petunia grows well in Ogle County County's temperate climate. Ogle County County averages a 173-day frost-free season, with last frost around April 23 and first frost around October 13.

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Your Ogle County Garden Planner — Free

A 22-page printable planner built for Ogle County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Ogle County, IL. Local conditions may vary. Last updated: June 2026.

Sources & credits

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