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When to Plant Petunia in Travis 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.

Travis County, Texas is in USDA Zone 9a. The average last spring frost is March 6 and the first fall frost is November 23, giving you a growing season of approximately 262 days.

At an elevation of 3,682 feet, Travis County receives approximately 66.3 inches of rainfall annually with predominantly clay soil. Summer highs average 92°F, providing good warmth for Petunia during the growing season. Clay soil retains moisture well for Petunia, but amend with compost to improve drainage and prevent root rot. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Petunia root diseases.

Annual Blooms in Summer Pollinator-friendly Fragrant
Travis County, TX (Zone 9a) Long season
262 days
Last Spring Frost March 6
262 growing days
First Fall Frost November 23
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Travis County Soil Profile

Soil Type

Clay

Soil pH

6.8-8.4

Drainage

Well Drained

Monthly Watering Guide for Petunia

Petunia needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Petunia Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 2" 0" ❄️ Dormant
Mar 4.3" 4.4" 0" ✅ Rainfall sufficient
Apr 4.3" 6.6" 0" ✅ Rainfall sufficient
May 4.3" 11.1" 0" ✅ Rainfall sufficient
Jun 4.3" 9.5" 0" ✅ Rainfall sufficient
Jul 4.3" 8.6" 0" ✅ Rainfall sufficient
Aug 4.3" 8.2" 0" ✅ Rainfall sufficient
Sep 4.3" 5.9" 0" ✅ Rainfall sufficient
Oct 4.3" 4.1" 0.2" 💧 Light watering
Nov 4.3" 2.5" 1.8" 💧 Light watering
Dec 1.8" 0" ❄️ Dormant

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

Petunia Planting Timeline — Travis County, TX

Petunia Planting Calendar

Activity When Date Range
Start Indoors January 9 Jan 9 – Jan 23
Transplant Outdoors February 20 Feb 20 – Mar 6
Bloom May 1 May 1 – Oct 2

· 12" apart · Rows 12" 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
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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 9a

📆 Growing Season

262 days in Travis County

Growing Tips for Travis 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 Travis County, TX?

Travis County is in Zone 9a with an average last frost of March 6. Plan your Petunia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Travis County, TX?

Travis County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is March 6 and first fall frost is November 23.

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Your Travis County Garden Planner — Free

A 22-page printable planner built for Travis County (Zone 9a). 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 Travis 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.