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When to Plant Impatiens in Frio County, TX

Frio County, Texas Zone 9a August

Frio County, Texas gardeners: here's your August plan

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

Avg. last frost February 26
Avg. first frost November 26
Soil temp (4") 80°F
Watering Low
Pest pressure High
Daylight 13 hrs
  1. It's harvest week for impatiens

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

Coming up in September — start thinking about
  • First harvests: impatiens

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Impatiens (Impatiens walleriana) are the go-to annual for shaded beds and containers. They produce a continuous carpet of flat-faced blooms from transplant until frost, needing little deadheading. Their preference for consistent moisture and part-shade makes them ideal under trees and along north-facing borders.

Frio County, Texas is in USDA Zone 9a. The average last spring frost is February 26 and the first fall frost is November 26, giving you a growing season of approximately 273 days.

At an elevation of 3,892 feet, Frio County receives approximately 51 inches of rainfall annually with predominantly loam soil. Summer highs average 93°F, providing good warmth for Impatiens during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Impatiens root diseases.

Annual Blooms in Summer Pollinator-friendly
Frio County, TX (Zone 9a) Year-round
273 days
Last Spring Frost February 26
273 growing days
First Fall Frost November 26

Frio County Soil Profile

Soil Type

Loam

Soil pH

6.4-7.2

Drainage

Well Drained

Impatiens Planting Risk Windows

Early Start (70% safe) ✓ Fits season (54 days to spare)
Start indoors: Dec 19 Transplant: Jan 30 🌸 Bloom: Apr 10 – Sep 25
Recommended (50%) ✓ Fits season (49 days to spare)
Start indoors: Jan 1 Transplant: Feb 12 🌸 Bloom: Apr 23 – Oct 8
Safe Start (90%) ✓ Fits season (42 days to spare)
Start indoors: Jan 24 Transplant: Mar 7 🌸 Bloom: May 16 – Oct 31

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 Frio County

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

Soil pH

Your soil pH (6.4–7.2) is more alkaline than Impatiens prefers (6.0–6.5). Add sulfur or peat moss to lower pH.

Soil Texture

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

Drainage

Drainage is adequate for Impatiens.

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Impatiens.

How to Plant Impatiens

10"
Between Plants
12"
Between Rows

Succession Planting Impatiens

5
successive plantings in your 273-day season

Sow every 6.9 weeks. Last sowing by Sep 12 to harvest before frost.

Impatiens Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.5″/week
Watering frequency 1-2 times/week
Season total 1,264 gal / 100 sq ft

Monthly Watering Guide for Impatiens

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

Month Impatiens Needs Rainfall You Supplement Action
Jan 1.2" 0" ❄️ Dormant
Feb 4.3" 1.9" 2.4" 🚿 Regular watering
Mar 4.3" 3.6" 0.7" 💧 Light watering
Apr 4.3" 4.9" 0" ✅ Rainfall sufficient
May 4.3" 7.5" 0" ✅ Rainfall sufficient
Jun 4.3" 9.4" 0" ✅ Rainfall sufficient
Jul 4.3" 6.3" 0" ✅ Rainfall sufficient
Aug 4.3" 5.2" 0" ✅ Rainfall sufficient
Sep 4.3" 4.6" 0" ✅ Rainfall sufficient
Oct 4.3" 3.4" 0.9" 💧 Light watering
Nov 4.3" 1.6" 2.7" 🚿 Regular watering
Dec 1.4" 0" ❄️ Dormant

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

Impatiens 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.

Impatiens needs ~1,333 GDD — county provides 5,411 GDD Excellent fit

Impatiens Planting Timeline — Frio County, TX

Impatiens Planting Calendar

Activity When Date Range
Start Indoors January 1 Jan 1 – Jan 15
Transplant Outdoors February 12 Feb 12 – Feb 26
Bloom April 23 Apr 23 – Oct 8

· 10" 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 Bloom
November
December

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

60–75 days

🧪 Soil pH

Needs 6–6.5 · Your soil: too_alkaline

🗺️ USDA Zone

Zone 9a

📆 Growing Season

273 days in Frio County

Growing Tips for Impatiens in Frio County

Direct sow Impatiens outdoors after February 26 in Frio County when soil has warmed and frost danger has passed.

General growing tips

Start seeds indoors 8–10 weeks before last frost at 70–75°F; germination requires light — do not cover seeds. Transplant after last frost once nights consistently exceed 50°F. Water regularly — wilting causes bud drop and they rarely fully recover the same flush. Watch for impatiens downy mildew (IDM); consider New Guinea impatiens as a resistant alternative in affected regions. Pinch tips at planting to encourage branching.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Impatiens in Frio County, TX?

Frio County is in Zone 9a with an average last frost of February 26. Plan your Impatiens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Frio County, TX?

Frio County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 26 and first fall frost is November 26.

🌱

Your Frio County Garden Planner — Free

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

Sources & credits

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