When to Plant Impatiens in Chattanooga, Tennessee (37421)

Location

Chattanooga, Tennessee

ZIP Code

37421

USDA Zone

Last Frost

Friday, March 20, 2026

📅 Your 2026 Planting Dates

Start Seeds Indoors

Friday, January 9, 2026

Transplant Outdoors

Friday, April 3, 2026

Based on last frost Friday, March 20, 2026 · Zone 8a

Pro tip: Start Impatiens seeds indoors 10 weeks before your last frost date, then transplant outdoors around Friday, April 3, 2026.

🌿 Plant Details

Scientific Name Impatiens walleriana

Days to Maturity 60 days

Mature Height 8-18"

Spread 12"

☀️ Growing Requirements

☀️

Sun

Partial to Full Shade (2-4 hours)

💧

Water

Regular (1-2 inches/week)

↔️

Spacing

8" apart

🌱

Planting Depth

0.125" deep

Seeds typically germinate in 14-21 days

Ready to Plant Impatiens in Chattanooga?

Get your seeds now so they're ready by Friday, January 9, 2026.

🛒 Buy on Amazon 🌿 True Leaf Market

* Affiliate links — we may earn a small commission at no extra cost to you.

🤝 Good Companions

BegoniaFernHostas

🤝

Full Companion Planting Guide for Impatiens

See which plants help Impatiens thrive, which to keep away, and raised bed layout tips →

🛠️ Supplies You'll Need

🌱 Seed Starting Trays 🪴 Seed Starting Mix 💡 Grow Lights 🌡️ Heat Mat 🌍 Flower Garden Soil ✂️ Pruning Shears 🚿 Watering Can

* Affiliate links — we may earn a small commission at no extra cost to you.

🌾 Seed Saving Guide

🟡 Moderate

⚠️ Many varieties are F1 hybrid — look for OP/heirloom types

When to Harvest Seed

Seed pods explode when touched — bag ripening pods with a rubber band before they burst.

Processing

Collect seeds from bags as pods burst. Tiny seeds — dry on paper towel for 1 week.

Seed Viability

Up to 2 years when stored cool, dark, and dry.

Pro Tip

Most garden impatiens are F1 hybrids. New Guinea impatiens are almost always hybrid — look for old-fashioned OP varieties.

🪴

Raised Bed Planting Guides

A 4×8 bed fits 72 plants of Impatiens. See plant counts, spacing grids, and companion pairings for every bed size →

Frequently Asked Questions

When should I plant Impatiens in Chattanooga, Tennessee? +

In Chattanooga (Zone 8a), start Impatiens seeds indoors around Friday, January 9, 2026 and transplant outdoors around Friday, April 3, 2026.

What is the last frost date for Chattanooga, Tennessee? +

The average last spring frost date for Chattanooga, Tennessee (ZIP 37421) is around Friday, March 20, 2026. This is based on NOAA climate normals for USDA Zone 8a.

How long does Impatiens take to grow? +

Impatiens typically matures in about 60 days from transplanting. In Chattanooga, that means you can expect harvest around Friday, April 3, 2026 plus 60 days.

Should I start Impatiens indoors or direct sow in Tennessee? +

Impatiens should be started indoors 10 weeks before your last frost date. In Chattanooga, that means starting around Friday, January 9, 2026.

📚 More Impatiens Planting Guides

🗺️

Impatiens in Tennessee

Zone-by-zone breakdown · Full state guide

→ 🌡️

Zone 8a Impatiens Guide

All cities in your zone · Avg dates

→

Other Plants for Chattanooga

Blackberry Blueberry Raspberry Strawberry Basil Chamomile Chives Cilantro Dill Lavender Lemon Balm Marjoram Mint Oregano Parsley Rosemary Sage Tarragon Thyme Acorn Squash Artichoke Arugula Asparagus Beefsteak Tomato Beet Bell Pepper Bok Choy Broccoli Brussels Sprout Butternut Squash Cabbage Cantaloupe Carrot Cauliflower Cayenne Pepper Celery Cherry Tomato Chili Pepper Collard Green Common Bean Cucumber Eggplant Endive Fennel Garlic Grape Tomato Green Bean Habanero Pepper Head Lettuce Heirloom Tomato Honeydew Melon Jalapeño Pepper Kale Kohlrabi Leaf Lettuce Leek Lima Bean Mustard Okra Onion Parsnip Pea Poblano Pepper Pole Pea Potato Pumpkin Radicchio Radish Rhubarb Roma Tomato Rutabaga Serrano Pepper Shallot Snap Pea Snow Pea Spaghetti Squash Spinach Squash Sweet Corn Sweet Potato Swiss Chard Tomato Turnip Watermelon Zucchini Sunflower Marigold Zinnia Nasturtium Cosmos Echinacea (Coneflower) Petunia Black-eyed Susan Apple Tree Pear Tree Peach Tree Plum Tree Sweet Cherry Tree Lemon Tree Borage Lemongrass Ginger Stevia Tomatillo Edamame Fava Bean Mâche Mizuna Sorrel Shishito Pepper Banana Pepper Watermelon Radish Napa Cabbage Popcorn Broccoli Raab Catnip Valerian Lemon Verbena Bee Balm Anise Lovage Chervil Summer Savory Dahlia Snapdragon Pansy Sweet Pea Morning Glory Hollyhock Larkspur Bachelor Button Columbine Salvia (Annual) Sweet Alyssum Celosia Lupine Verbena Elderberry Grape Vine Red Currant Gooseberry Serviceberry Fig Tree Avocado Tree Persimmon Tree Olive Tree

Growing Impatiens in Zone 8a

Impatiens (Impatiens walleriana) is a popular garden vegetable. In Chattanooga, Tennessee, which is in USDA Hardiness Zone 8a, you should start seeds indoors around Friday, January 9, 2026.

Your average last frost date is Friday, March 20, 2026. Plan to transplant your Impatiens seedlings outdoors around Friday, April 3, 2026, about 2 weeks after your last frost date.