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When to Plant Geraniums in Dallas County, TX

Dallas County, Texas Zone 8b June

June in Dallas County, Texas — your action list

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

Avg. last frost March 8
Avg. first frost November 20
Soil temp (4") 82°F
Watering Low
Pest pressure High
Daylight 14.1 hrs
  1. It's harvest week for geraniums

    Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.

Get ahead of 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.

Dallas County, Texas is in USDA Zone 8b. The average last spring frost is March 8 and the first fall frost is November 20, giving you a growing season of approximately 257 days.

At an elevation of 67 feet, Dallas County receives approximately 65.7 inches of rainfall annually with predominantly clay soil. Summer highs average 97°F, so Geraniums may need afternoon shade and extra watering during peak heat. Clay soil retains moisture well for Geraniums, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Geraniums root diseases.

Annual Blooms in Multi-season Pollinator-friendly Deer-resistant Good for cutting Fragrant
Dallas County, TX (Zone 8b) Long season
257 days
Last Spring Frost March 8
257 growing days
First Fall Frost November 20
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Dallas County Soil Profile

Soil Type

Clay

Soil pH

6.7-8.4

Drainage

Well Drained

Geraniums Planting Risk Windows

Early Start (70% safe) ✓ Fits season (44 days to spare)
Start indoors: Dec 21 Transplant: Feb 15 🌸 Bloom: Apr 26 – Sep 27
Recommended (50%) ✓ Fits season (47 days to spare)
Start indoors: Dec 28 Transplant: Feb 22 🌸 Bloom: May 3 – Oct 4
Safe Start (90%) ✓ Fits season (32 days to spare)
Start indoors: Jan 29 Transplant: Mar 26 🌸 Bloom: Jun 4 – Nov 5

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 Dallas County

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

Soil pH

Your soil pH (6.7–8.4) is more alkaline than Geraniums prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Heavy clay soil (48% clay) in Dallas County compacts easily and drains slowly. Amend with compost and avoid working soil when wet.

Organic Matter

Organic matter is moderate (2.6%). Annual compost additions will help Geraniums.

How to Plant Geraniums

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

Succession Planting Geraniums

4
successive plantings in your 257-day season

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

Geraniums Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 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 1.5" 0" ❄️ Dormant
Feb 2.5" 0" ❄️ Dormant
Mar 4.3" 4.4" 0" ✅ Rainfall sufficient
Apr 4.3" 7.1" 0" ✅ Rainfall sufficient
May 4.3" 9.2" 0" ✅ Rainfall sufficient
Jun 4.3" 10.4" 0" ✅ Rainfall sufficient
Jul 4.3" 7.4" 0" ✅ Rainfall sufficient
Aug 4.3" 8.3" 0" ✅ Rainfall sufficient
Sep 4.3" 6" 0" ✅ Rainfall sufficient
Oct 4.3" 4.6" 0" ✅ Rainfall sufficient
Nov 4.3" 2.4" 1.9" 💧 Light watering
Dec 1.7" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Dallas 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 ~1,934 GDD — county provides 5,846 GDD Excellent fit

Geraniums Planting Timeline — Dallas County, TX

Geraniums Planting Calendar

Activity When Date Range
Start Indoors December 28 Dec 28 – Jan 11
Transplant Outdoors February 22 Feb 22 – Mar 8
Bloom May 3 May 3 – Oct 4

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

70–100 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 8b

📆 Growing Season

257 days in Dallas County

Growing Tips for Geraniums in Dallas County

Direct sow Geraniums outdoors after March 08 in Dallas County when soil has warmed and frost danger has passed.

With Dallas County's clay soil (48% clay), work in 3-4 inches of compost before planting Geraniums. Avoid tilling when soil is wet to prevent compaction.

With summer highs reaching 97°F in Dallas County, provide afternoon shade for Geraniums and water deeply in the morning.

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 Dallas County, TX?

Dallas County is in Zone 8b with an average last frost of March 8. Plan your Geraniums planting based on this frost date — see the calendar above for exact timing.

What planting zone is Dallas County, TX?

Dallas County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 8 and first fall frost is November 20.

🌱

Your Dallas County Garden Planner — Free

A 22-page printable planner built for Dallas County (Zone 8b). 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 Dallas County, TX. 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.