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When to Plant Petunia in Lee County, TX

Lee County, Texas Zone 9a July

Your July game plan for Lee County, Texas

We've pulled the most time-sensitive tasks for Lee County, Texas this July and put them front and centre. Tackle them in order.

Avg. last frost February 28
Avg. first frost November 30
Soil temp (4") 90°F
Watering Low
Pest pressure High
Daylight 13.8 hrs
  1. Pick petunia

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

A few tasks this July that'll pay off in August
  • First harvests: petunia

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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.

Lee County, Texas is in USDA Zone 9a. The average last spring frost is February 28 and the first fall frost is November 30, giving you a growing season of approximately 275 days.

At an elevation of 1,174 feet, Lee County receives approximately 59.1 inches of rainfall annually with predominantly clay soil. Summer highs average 97°F, so Petunia may need afternoon shade and extra watering during peak heat. 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
Lee County, TX (Zone 9a) Year-round
275 days
Last Spring Frost February 28
275 growing days
First Fall Frost November 30

Lee County Soil Profile

Soil Type

Clay

Soil pH

7.1-8.2

Drainage

Well Drained

Petunia Planting Risk Windows

Early Start (70% safe) ✓ Fits season (65 days to spare)
Start indoors: Dec 20 Transplant: Jan 31 🌸 Bloom: Apr 11 – Sep 12
Recommended (50%) ✓ Fits season (65 days to spare)
Start indoors: Jan 3 Transplant: Feb 14 🌸 Bloom: Apr 25 – Sep 26
Safe Start (90%) ✓ Fits season (58 days to spare)
Start indoors: Jan 27 Transplant: Mar 10 🌸 Bloom: May 19 – Oct 20

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 Lee County

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

Soil pH

Your soil pH (7.1–8.2) is more alkaline than Petunia prefers (6.0–7.0). Add sulfur or peat moss to lower pH.

Soil Texture

Your clay soil in Lee County is workable for Petunia. Add compost annually to improve structure.

Organic Matter

Organic matter is moderate (2.7%). Annual compost additions will help Petunia.

How to Plant Petunia

12"
Between Plants
12"
Between Rows

Succession Planting Petunia

4
successive plantings in your 275-day season

Sow every 8 weeks. Last sowing by Sep 01 to harvest before frost.

Petunia 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 247 gal / 100 sq ft

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 4.3" 1.8" 2.5" 🚿 Regular watering
Mar 4.3" 4.3" 0" ✅ Rainfall sufficient
Apr 4.3" 5.8" 0" ✅ Rainfall sufficient
May 4.3" 8.6" 0" ✅ Rainfall sufficient
Jun 4.3" 9.5" 0" ✅ Rainfall sufficient
Jul 4.3" 8.1" 0" ✅ Rainfall sufficient
Aug 4.3" 7.3" 0" ✅ Rainfall sufficient
Sep 4.3" 5.2" 0" ✅ Rainfall sufficient
Oct 4.3" 3.4" 0.9" 💧 Light watering
Nov 4.3" 1.8" 2.5" 🚿 Regular watering
Dec 1.7" 0" ❄️ Dormant

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

Petunia 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.

Petunia needs ~1,820 GDD — county provides 6,279 GDD Excellent fit

Petunia Planting Timeline — Lee County, TX

Petunia Planting Calendar

Activity When Date Range
Start Indoors January 3 Jan 3 – Jan 17
Transplant Outdoors February 14 Feb 14 – Feb 28
Bloom April 25 Apr 25 – Sep 26

· 12" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

70–90 days

🧪 Soil pH

Needs 6–7 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 9a

📆 Growing Season

275 days in Lee County

Growing Tips for Petunia in Lee County

Direct sow Petunia outdoors after February 28 in Lee County when soil has warmed and frost danger has passed.

With Lee County's clay soil (37% clay), work in 3-4 inches of compost before planting Petunia. Avoid tilling when soil is wet to prevent compaction.

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

Common pests for Petunia in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

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 Lee County, TX?

Lee County is in Zone 9a with an average last frost of February 28. Plan your Petunia planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lee County, TX?

Lee County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 28 and first fall frost is November 30.

🌱

Your Lee County Garden Planner — Free

A 22-page printable planner built for Lee 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 Lee County, TX. Local conditions may vary. Last updated: July 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.