July 04, 2025

How to Start Seeds Indoors in 8 Simple Steps

Starting seeds indoors is a fantastic way to get a jump-start on the growing season, save money, and enjoy the satisfaction of watching your plants grow from the very beginning. Whether you're new to gardening or just looking to improve your technique, this guide walks you through the process in eight simple steps. It’s easier than you might think, and it can actually be pretty fun once you get going.

Step 1: Choose the Right Seeds
Before anything else, decide what you want to grow. Look for seed packets labeled "ideal for starting indoors." Some vegetables and herbs, like tomatoes, peppers, broccoli, lettuce, and basil, do particularly well when started inside. Make sure the seeds are fresh and within their viable planting window. Check the back of the seed packet for recommendations about when to start them based on your growing zone.

Step 2: Pick the Right Containers
You don’t need anything fancy to start seeds. You can use seed trays, small pots, yogurt cups, egg cartons, or even cut-off milk jugs. Just make sure whatever you use has drainage holes at the bottom. This prevents excess water from causing root rot. Place a tray or plastic lid underneath to catch any drips.

Step 3: Use High-Quality Seed Starting Mix
Regular garden soil is too heavy for seedlings. It tends to compact and can contain pests or diseases. Use a seed starting mix, which is lighter, drains well, and helps delicate seedlings grow strong roots. You can find it at garden centers or make your own with a mix of peat moss or coco coir, vermiculite, and perlite.

Step 4: Moisten the Soil Before Planting
Before adding soil to your containers, moisten the seed starting mix so it’s damp but not soaking wet. This makes it easier for seeds to settle in and begin growing. Think of it like a wrung-out sponge. Add the damp mix to your containers and gently pat it down without compacting it too much.

Step 5: Plant Your Seeds
Now the fun part begins. Read the seed packet to determine how deep to plant your seeds. A general rule is to plant them twice as deep as they are wide. Press the seed gently into the soil and cover it lightly. You can plant two or three seeds per cell or container, then thin them out later if needed.

Step 6: Keep Things Warm and Humid
Seeds need warmth to germinate. Most do best in temperatures between 65 and 75 degrees Fahrenheit. If your home is chilly, use a seedling heat mat to warm the soil from underneath. To maintain humidity, cover the trays with a plastic dome or plastic wrap until the seeds sprout. Be sure to remove the cover once the seedlings emerge to prevent mold.

Step 7: Provide Plenty of Light
After your seeds sprout, they need lots of light. A sunny windowsill might work, but many gardeners use grow lights to ensure their seedlings get enough brightness. Place the lights about 2 to 3 inches above the seedlings and keep them on for 12 to 16 hours a day. Without enough light, seedlings can become leggy and weak.

Step 8: Water and Care for Your Seedlings
Keep the soil moist but not soggy. Use a spray bottle or gentle watering can to avoid disturbing the young roots. As the seedlings grow, thin them by snipping the weaker ones at the soil line so the strongest plant can thrive. Once they develop two or more sets of true leaves, you can start feeding them with a diluted liquid fertilizer.

Bonus Tip: Harden Off Before Transplanting
Before moving your seedlings outdoors, give them time to adjust. Start by placing them outside in a shaded spot for a few hours each day, gradually increasing the time and sunlight over a week or two. This hardening-off process helps prevent shock and gives your plants the best chance to thrive in the garden.

With a little time, patience, and care, you’ll have strong, healthy seedlings ready to move outdoors when the weather warms up. Starting seeds indoors is a rewarding way to kick off the growing season and a great activity for anyone who loves to see things grow.