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When to Plant Geraniums in Kerr County, TX

Kerr County, Texas Zone 8b June

Your June game plan for Kerr County, Texas

June rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Kerr County, Texas.

Avg. last frost March 24
Avg. first frost November 11
Soil temp (4") 75°F
Watering Low
Pest pressure High
Daylight 13.9 hrs
  1. Start geraniums under lights

    Starting these indoors now means sturdy transplants ready the moment your soil warms up.

  2. Harvest geraniums as they ripen

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

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.

Kerr County, Texas is in USDA Zone 8b. The average last spring frost is March 24 and the first fall frost is November 11, giving you a growing season of approximately 232 days.

At an elevation of 3,907 feet, Kerr County receives approximately 52 inches of rainfall annually with predominantly loam soil. Summer highs average 93°F, providing good warmth for Geraniums during the growing season. 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
Kerr County, TX (Zone 8b) Long season
232 days
Last Spring Frost March 24
232 growing days
First Fall Frost November 11
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Kerr County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.6

Drainage

Well Drained

Geraniums Planting Risk Windows

Early Start (70% safe) ✓ Fits season (23 days to spare)
Start indoors: Jan 1 Transplant: Feb 26 🌸 Bloom: May 7 – Oct 8
Recommended (50%) ✓ Fits season (22 days to spare)
Start indoors: Jan 13 Transplant: Mar 10 🌸 Bloom: May 19 – Oct 20
Safe Start (90%) ✓ Fits season (16 days to spare)
Start indoors: Feb 5 Transplant: Apr 2 🌸 Bloom: Jun 11 – Nov 12

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 Kerr County

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

Soil pH

Your soil pH (6.4–7.6) overlaps with Geraniums's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.2%). 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 232-day season

Sow every 8 weeks. Last sowing by Aug 03 to harvest before frost.

Geraniums Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 121 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 1.2" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 4.3" 3.4" 0.9" 💧 Light watering
Apr 4.3" 5.7" 0" ✅ Rainfall sufficient
May 4.3" 6.7" 0" ✅ Rainfall sufficient
Jun 4.3" 9.2" 0" ✅ Rainfall sufficient
Jul 4.3" 7.3" 0" ✅ Rainfall sufficient
Aug 4.3" 6.1" 0" ✅ Rainfall sufficient
Sep 4.3" 4.8" 0" ✅ Rainfall sufficient
Oct 4.3" 3.1" 1.2" 💧 Light watering
Nov 4.3" 1.7" 2.6" 🚿 Regular watering
Dec 1.3" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Kerr 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 ~1,679 GDD — county provides 4,582 GDD Excellent fit

Geraniums Planting Timeline — Kerr County, TX

Geraniums Planting Calendar

Activity When Date Range
Start Indoors January 13 Jan 13 – Jan 27
Transplant Outdoors March 10 Mar 10 – Mar 24
Bloom May 19 May 19 – Oct 20

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

Month-by-Month Timeline

MonthActivities
January Start Indoors
February
March Transplant Outdoors
April
May Bloom
June Bloom
July Bloom
August Bloom
September Bloom
October Bloom
November
December
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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 8b

📆 Growing Season

232 days in Kerr County

Growing Tips for Geraniums in Kerr County

Direct sow Geraniums outdoors after March 24 in Kerr 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 Kerr County, TX?

Kerr County is in Zone 8b with an average last frost of March 24. Plan your Geraniums planting based on this frost date — see the calendar above for exact timing.

What planting zone is Kerr County, TX?

Kerr County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 24 and first fall frost is November 11.

🌱

Your Kerr County Garden Planner — Free

A 22-page printable planner built for Kerr 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 Kerr 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.