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When to Plant Petunia in Kleberg County, TX

Petunias (Petunia x hybrida) are warm-season tender annuals prized for their prolific, trumpet-shaped blooms in nearly every color. They perform from hanging baskets to garden borders and bloom continuously from late spring until frost, provided spent flowers are removed regularly.

Kleberg County, Texas is in USDA Zone 9b. The average last spring frost is February 13 and the first fall frost is December 9, giving you a growing season of approximately 299 days.

At an elevation of 1,079 feet, Kleberg County receives approximately 64.4 inches of rainfall annually with predominantly loam soil. Summer highs average 102°F, so Petunia may need afternoon shade and extra watering during peak heat. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Petunia root diseases.

Annual Blooms in Summer Pollinator-friendly Fragrant
Kleberg County, TX (Zone 9b) Year-round
299 days
Last Spring Frost February 13
299 growing days
First Fall Frost December 9

Kleberg County Soil Profile

Soil Type

Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Petunia Planting Timeline — Kleberg County, TX

Petunia Planting Calendar

Activity When Date Range
Start Indoors December 19 Dec 19 – Jan 2
Transplant Outdoors January 23 Jan 23 – Feb 6
Bloom April 3 Apr 3 – Sep 18

· 12" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 9b

📆 Growing Season

299 days in Kleberg County

Growing Tips for Kleberg County

Start seeds indoors 8–10 weeks before last frost; seeds need light to germinate — press onto moist mix surface, do not cover. Transplant after last frost once nights stay above 50°F. Pinch back leggy plants mid-summer to encourage bushy re-bloom. Wave/spreading types tolerate light shade but bloom less. Feed every 2 weeks with balanced fertilizer once established.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Petunia in Kleberg County, TX?

Kleberg County is in Zone 9b with an average last frost of February 13. Plan your Petunia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Kleberg County, TX?

Kleberg County, Texas is in USDA Hardiness Zone 9b. The average last spring frost is February 13 and first fall frost is December 9.

🌱

Your Kleberg County Garden Planner — Free

A 22-page printable planner built for Kleberg County (Zone 9b). 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 Kleberg County, TX. Local conditions may vary. Last updated: June 2026.

Sources & credits

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