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When to plant Geraniums in Hampton, IL

Plant Geraniums in Hampton, between April 22 and May 6 — the only viable window. Zone 5b's short season (187 frost-free days) rules out a fall crop.

When to Plant Geraniums in Hampton, 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.

Hampton, Illinois is in USDA Zone 5b. The average last spring frost is April 15 and the first fall frost is October 19, giving you a growing season of approximately 187 days.

At an elevation of 1,172 feet, Rock Island County receives approximately 35.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Geraniums to ensure they mature before fall.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Hampton, IL (Zone 5b) Moderate season
187 days
Last Spring Frost April 15
187 growing days
First Fall Frost October 19

Hampton Soil Profile

Soil Type

Silt Loam

Soil pH

6.3-6.9

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 1.7" 0" ❄️ Dormant
Feb 1.4" 0" ❄️ Dormant
Mar 2.2" 0" ❄️ Dormant
Apr 4.3" 3.6" 0.7" 💧 Light watering
May 4.3" 4.2" 0.1" 💧 Light watering
Jun 4.3" 4.7" 0" ✅ Rainfall sufficient
Jul 4.3" 3.5" 0.8" 💧 Light watering
Aug 4.3" 4.2" 0.1" 💧 Light watering
Sep 4.3" 2.7" 1.6" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 2.6" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

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

Geraniums Planting Timeline — Hampton, IL

Geraniums Planting Calendar

Activity When Date Range
Start Indoors February 4 Feb 4 – Feb 18
Transplant Outdoors April 22 Apr 22 – May 6
Bloom July 1 Jul 1 – Sep 23

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

Month-by-Month Timeline

MonthActivities
January
February Start Indoors
March
April Transplant Outdoors
May Transplant Outdoors
June
July Bloom
August Bloom
September Bloom
October
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 5b

📆 Growing Season

187 days in Rock Island County

Growing Tips for Hampton

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 →

When should I plant Geraniums in Hampton, IL?

In Hampton, IL, plant Geraniums after the last frost (around April 15) and before the first frost (around October 19). Best results when soil holds above 50°F.

What growing zone is Hampton, IL for Geraniums?

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

Can Geraniums grow in Hampton's climate?

Yes — Geraniums grows well in Hampton's temperate climate. Hampton averages a 187-day frost-free season, with last frost around April 15 and first frost around October 19.

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Your Rock Island County Garden Planner — Free

A 22-page printable planner built for Rock Island 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.

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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 Rock Island County, IL. Local conditions may vary. Last updated: July 2026.