How to Start Seeds Indoors: A Beginner’s Guide to Successful Growth

Want to start your garden from seeds but aren’t sure where to begin? This step-by-step guide will walk you through everything you need to know to start seeds indoors successfully!

This post contains affiliate links for your convenience. I may earn a small commission from qualifying purchases at no extra cost to you. Read my full disclaimer here.

Why Start Your Garden from Seeds?

Starting your garden from seed gives you complete control over how your plants are grown—from seed to harvest. You can choose organic, heirloom, or specialty varieties that aren’t always available at local nurseries. Plus, it’s a more affordable way to grow a lush, productive garden!

When to Start Seeds Indoors

The best time to start seeds indoors depends on your last frost date and the type of plants you’re growing.

Some seeds, like tomatoes and peppers, can be started 6-8 weeks before the last frost. Others, like cucumbers and squash, need just 2-4 weeks.

Check the seed packet for the recommended number of weeks. To find your personal seed starting timeline:

• Look up your last frost date here.
• Count backward from that date based on the seed packet instructions.

Tip: This handy planting schedule from the Farmer’s almanac is very helpful.

How to Start Seeds Indoors (Step-by-Step)

Here’s what you’ll need:

• Seeds
• Water
• Seed starting mix (or loose potting soil)
• Seed starter trays (with drainage holes)
• Plant labels (so you don’t mix up your seedlings)
• Bin or tray (for pre-moistening the soil)
• Sunny window or grow lights
• Humidity dome (optional but helpful for germination)

Want an easy start? Grab an all-in-one seed-starting kit.

Save on quality seed from Epic Gardening with the code: HOMESTEADMOTHER

Here’s what you do:

1. Prep the Soil

Pour your seed starting mix into a bin and add water, just enough to moisten the soil. You don’t want it to be soaking wet.

Tip: If you squeeze a handful and it holds shape without dripping, it’s perfect.

2. Fill the Seed Trays

Fill each seed-starting cell with the moist soil mix, lightly pressing it in. Don’t pack it too tightly to make it easier for the roots to grow.

3. Plant the Seeds

• Place 1-3 seeds per cell and gently cover them with soil.
• Tiny seeds (like mint and celery) can be left uncovered on the soil surface.
• Label each row so you know what’s what!

4. Provide Light & Warmth

Place your trays in a warm, sunny spot. A south-facing window is ideal. If you don’t have a window that receives direct sunlight, you can use grow lights to ensure your seedlings are getting enough light.

Tip: A heat mat can speed up germination for heat-loving plants like peppers.

5. Keep the Soil Moist.

Seeds need consistent moisture to sprout. I highly recommend bottom watering. This method helps prevent overwatering by allowing the roots to soak up water as they need it.

To bottom water, just pour an inch of water into the bottom tray as needed, usually about once a week.

Tip: Use a humidity dome to trap moisture and speed up germination. Remove for the dome once seedlings emerge.

6. Thin Out the Seedlings

Once your seedlings develop their first set of leaves they should be thinned out. Keep the strongest seedling in each cell and gently remove the weaker ones.

Tip: Gently snip the weaker ones at the base with scissors instead of pulling them out to prevent damaging the roots of the other seedlings.

7. Pot Them up When They’re Ready

As your seedlings grow, they’ll outgrow their starter trays. When you see roots coming out of the bottom it is time to transplant them into larger nursery pots.

Get ready to grow!

Watching tiny seeds you planted grow into strong, healthy plants is one of the most rewarding parts of gardening. Starting from seed not only gives you a head start on the season, but also a deeper connection to your garden.

Share your garden with me!

Tag @thehomesteadmother on Instagram to share your seed-starting journey —I’d love to see what you’re growing!

Trouble starting seeds? Check out these helpful posts:

• 7 Mistakes Beginner Gardeners Make When Starting Seeds (and How to Avoid Them)
• Direct Sowing Seeds: What Seeds to Sow and When

Happy growing & until next time –

Love this post? Save it for later!