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When to plant Geraniums in Dearborn County, IN

Dearborn County's 187-day season only supports one Geraniums planting per year. Sow between April 23 and May 7 for the best chance at full maturity before October 20.

When to Plant Geraniums in Dearborn County, IN

Dearborn County, Indiana Zone 6b June

June in Dearborn County, Indiana — your action list

June is a pivotal month for Dearborn County, Indiana gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost April 16
Avg. first frost October 20
Soil temp (4") 71°F
Watering Moderate
Pest pressure High
Daylight 14.7 hrs
  1. Sow geraniums in trays indoors

    These need a head start before your last frost (April 16). Sow into cells now so you're ready to transplant in a few weeks.

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

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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.

Dearborn County, Indiana is in USDA Zone 6b. The average last spring frost is April 16 and the first fall frost is October 20, giving you a growing season of approximately 187 days.

At an elevation of 1,290 feet, Dearborn County receives approximately 32.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85°F, providing good warmth for Geraniums during the growing season.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Dearborn County, IN (Zone 6b) Moderate season
187 days
Last Spring Frost April 16
187 growing days
First Fall Frost October 20

Dearborn County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-7.3

Drainage

Well Drained

Geraniums Planting Risk Windows

Early Start (70% safe) ✓ Fits season (15 days to spare)
Start indoors: Jan 29 Transplant: Apr 16 🌸 Bloom: Jun 25 – Oct 1
Recommended (50%) ✓ Fits season (12 days to spare)
Start indoors: Feb 5 Transplant: Apr 23 🌸 Bloom: Jul 2 – Oct 8
Safe Start (90%) ✓ Fits season (9 days to spare)
Start indoors: Feb 20 Transplant: May 8 🌸 Bloom: Jul 17 – Oct 23

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 Dearborn County

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

Soil pH

Your soil pH (5.9–7.3) overlaps with Geraniums's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.9%). Annual compost additions will help Geraniums.

How to Plant Geraniums

0.1"
Planting Depth
12"
Between Plants
14"
Between Rows

Succession Planting Geraniums

3
successive plantings in your 187-day season

Sow every 8 weeks. Last sowing by Jul 12 to harvest before frost.

Geraniums Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 453 gal / 100 sq ft

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 1.5" 0" ❄️ Dormant
Mar 2.1" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 4" 0.3" 💧 Light watering
Jun 4.3" 3.7" 0.6" 💧 Light watering
Jul 4.3" 4.2" 0.1" 💧 Light watering
Aug 4.3" 3" 1.3" 💧 Light watering
Sep 4.3" 2.7" 1.6" 💧 Light watering
Oct 4.3" 2.5" 1.8" 💧 Light watering
Nov 2.4" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

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

Geraniums 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.

Geraniums needs ~1,169 GDD — county provides 2,571 GDD Excellent fit

Geraniums Planting Timeline — Dearborn County, IN

Geraniums Planting Calendar

Activity When Date Range
Start Indoors February 5 Feb 5 – Feb 19
Transplant Outdoors April 23 Apr 23 – May 7
Bloom July 2 Jul 2 – Oct 8

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 Bloom
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6b

📆 Growing Season

187 days in Dearborn County

Growing Tips for Geraniums in Dearborn County

Direct sow Geraniums outdoors after April 16 in Dearborn County when soil has warmed and frost danger has passed.

General growing tips

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 Dearborn County, IN?

Dearborn County is in Zone 6b with an average last frost of April 16. Plan your Geraniums planting based on this frost date — see the calendar above for exact timing.

What planting zone is Dearborn County, IN?

Dearborn County, Indiana is in USDA Hardiness Zone 6b. The average last spring frost is April 16 and first fall frost is October 20.

When should I plant Geraniums in Dearborn County, IN?

In Dearborn County, IN, plant Geraniums after the last frost (around April 16) and before the first frost (around October 20). Best results when soil holds above 50°F.

What growing zone is Dearborn County, IN for Geraniums?

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

Can Geraniums grow in Dearborn County's climate?

Yes — Geraniums grows well in Dearborn County's temperate climate. Dearborn County averages a 187-day frost-free season, with last frost around April 16 and first frost around October 20.

🌱

Your Dearborn County Garden Planner — Free

A 22-page printable planner built for Dearborn 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 Dearborn County, IN. 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.