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When to plant Geraniums in Jo Daviess County, IL

Jo Daviess County's short 170-day growing season means one Geraniums planting between May 1 and May 15. No fall crop in Zone 5a.

When to Plant Geraniums in Jo Daviess County, IL

Geraniums (Pelargonium × hortorum) are tender perennials grown as warm-season annuals throughout North America. Prized for their bold flower clusters, long bloom period, and tolerance of summer heat when planted in well-drained soil, they anchor window boxes, containers, and bed borders from late spring until hard frost. Zones 9b–11b can overwinter plants in the ground.

Jo Daviess County, Illinois is in USDA Zone 5a. The average last spring frost is April 24 and the first fall frost is October 11, giving you a growing season of approximately 170 days.

At an elevation of 501 feet, Jo Daviess County receives approximately 35.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Geraniums during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Jo Daviess County, IL (Zone 5a) Moderate season
170 days
Last Spring Frost April 24
170 growing days
First Fall Frost October 11

Jo Daviess County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.3

Drainage

Well Drained

Monthly Watering Guide for Geraniums

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

Month Geraniums Needs Rainfall You Supplement Action
Jan 1.3" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 4.3" 0" ✅ Rainfall sufficient
Jun 4.3" 4.3" 0" ✅ Rainfall sufficient
Jul 4.3" 4.2" 0.1" 💧 Light watering
Aug 4.3" 3.9" 0.4" 💧 Light watering
Sep 4.3" 3.1" 1.2" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 2.2" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

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

Geraniums Planting Timeline — Jo Daviess County, IL

Geraniums Planting Calendar

Activity When Date Range
Start Indoors February 13 Feb 13 – Feb 27
Transplant Outdoors May 1 May 1 – May 15
Bloom July 10 Jul 10 – Oct 2

Plant 0.1" deep · 12" apart · Rows 14" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5a

📆 Growing Season

170 days in Jo Daviess County

Growing Tips for Jo Daviess County

Start seeds indoors 10–12 weeks before last frost — germination is slow and erratic without bottom heat (70–75°F). Transplant after frost danger passes. Geraniums rarely direct-sown; cuttings or transplants are the standard. Deadhead spent umbels weekly to maintain continuous bloom. Let soil dry slightly between waterings to prevent root rot. In zones 10–11 plants may be left in ground year-round or overwintered as houseplants.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Geraniums in Jo Daviess County, IL?

Jo Daviess County is in Zone 5a with an average last frost of April 24. Plan your Geraniums planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jo Daviess County, IL?

Jo Daviess County, Illinois is in USDA Hardiness Zone 5a. The average last spring frost is April 24 and first fall frost is October 11.

When should I plant Geraniums in Jo Daviess County, IL?

In Jo Daviess County, IL, plant Geraniums after the last frost (around April 24) and before the first frost (around October 11). Best results when soil holds above 50°F.

What growing zone is Jo Daviess County, IL for Geraniums?

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

Can Geraniums grow in Jo Daviess County's climate?

Yes — Geraniums grows well in Jo Daviess County's temperate climate. Jo Daviess County averages a 170-day frost-free season, with last frost around April 24 and first frost around October 11.

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Your Jo Daviess County Garden Planner — Free

A 22-page printable planner built for Jo Daviess County (Zone 5a). 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 Jo Daviess County, IL. Local conditions may vary. Last updated: July 2026.

Sources & credits

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