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When to Plant Impatiens in Johnson County, TN

Johnson County, Tennessee Zone 7a July

July in Johnson County, Tennessee — your action list

Each item below is timed to Johnson County, Tennessee's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost April 14
Avg. first frost October 22
Soil temp (4") 80°F
Watering Low
Pest pressure High
Daylight 14.3 hrs
  1. Collect impatiens at their peak

    If you can't use it all right away, check the food-preservation section of your planner.

Looking ahead to August
  • 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.

Johnson County, Tennessee is in USDA Zone 7a. The average last spring frost is April 14 and the first fall frost is October 22, giving you a growing season of approximately 191 days.

At an elevation of 404 feet, Johnson County receives approximately 43.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Impatiens during the growing season.

Annual Blooms in Summer Pollinator-friendly
Johnson County, TN (Zone 7a) Moderate season
191 days
Last Spring Frost April 14
191 growing days
First Fall Frost October 22

Johnson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-7.1

Drainage

Well Drained

Impatiens Planting Risk Windows

Early Start (70% safe) ✓ Fits season (2 days to spare)
Start indoors: Feb 12 Transplant: Apr 16 🌸 Bloom: Jun 25 – Oct 15
Recommended (50%) ✓ Fits season (2 days to spare)
Start indoors: Feb 17 Transplant: Apr 21 🌸 Bloom: Jun 30 – Oct 20
Safe Start (90%) ✗ May not fit
Start indoors: Mar 9 Transplant: May 11 🌸 Bloom: Jul 20 – Nov 9

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 Johnson County

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

Soil pH

Your soil pH (5.7–7.1) overlaps with Impatiens's range (6.0–6.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.5%). Annual compost additions will help Impatiens.

How to Plant Impatiens

10"
Between Plants
12"
Between Rows

Succession Planting Impatiens

3
successive plantings in your 191-day season

Sow every 6.9 weeks. Last sowing by Aug 08 to harvest before frost.

Impatiens Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 102 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 4" 0" ❄️ Dormant
Feb 3.4" 0" ❄️ Dormant
Mar 4.5" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 3.7" 0.6" 💧 Light watering
Jun 4.3" 3.4" 0.9" 💧 Light watering
Jul 4.3" 4" 0.3" 💧 Light watering
Aug 4.3" 4.2" 0.1" 💧 Light watering
Sep 4.3" 3.5" 0.8" 💧 Light watering
Oct 4.3" 2.8" 1.5" 💧 Light watering
Nov 3" 0" ❄️ Dormant
Dec 3.7" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Johnson 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 ~979 GDD — county provides 2,769 GDD Excellent fit

Impatiens Planting Timeline — Johnson County, TN

Impatiens Planting Calendar

Activity When Date Range
Start Indoors February 17 Feb 17 – Mar 3
Transplant Outdoors April 21 Apr 21 – May 5
Bloom June 30 Jun 30 – Oct 20

· 10" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

60–75 days

🧪 Soil pH

Needs 6–6.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 7a

📆 Growing Season

191 days in Johnson County

Growing Tips for Impatiens in Johnson County

Direct sow Impatiens outdoors after April 14 in Johnson 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 Johnson County, TN?

Johnson County is in Zone 7a with an average last frost of April 14. Plan your Impatiens planting based on this frost date — see the calendar above for exact timing.

What planting zone is Johnson County, TN?

Johnson County, Tennessee is in USDA Hardiness Zone 7a. The average last spring frost is April 14 and first fall frost is October 22.

🌱

Your Johnson County Garden Planner — Free

A 22-page printable planner built for Johnson County (Zone 7a). 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 Johnson County, TN. 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.