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How To Make Homemade Seed Starting Soil – Create Perfect Soil To Grow Great Plants!

One of the best ways to grow healthy, strong plants from seed is to start them in loose, healthy and fertile soil – and there is no better way to do that than to make your own incredible homemade seed starting soil right at home!

Growing your own transplants from seed is one of the best ways to save money when gardening. Even better, it gives you the opportunity to grow all kinds of amazing plants you can’t find locally. After all, most nurseries and plant stores are only going to carry the most popular of plants.

But perhaps best of all, growing your own plants from seed lets you create incredibly strong and healthy transplants that are ready to grow like crazy when you plant them outdoors. And that process all begins with planting your seeds in the best soil possible.

Several seedlings in seed starting trays with loose seed starting soil.
Using your own homemade seed starting soil allows you to have more control over the ingredients as well as the density of the soil. The end result is seeds that germinate and grow better – and faster.
Giving Your Seeds The Best Soil To Germinate & Grow

One of the biggest mistakes gardeners make when trying to start plants indoors is to use the wrong soil. Top soil or soil from the garden are both too dense and heavy for good germination. These heavier soils don’t allow seeds or seedlings to easily absorb nutrients. They also usually hold too much water, making it easy for seeds to rot before they ever germinate.

Unfortunately, potting soil isn’t the best solution either. Although potting soil contains more nutrients and is definitely lighter than regular garden dirt and topsoil, it still isn’t light enough for starting and growing seedlings. Nor does it contain the best power to promote early seed growth.

The good news is that potting soil’s lighter structure and density are a great starting point for creating an excellent homemade seed starting soil. And by simply adding just a few additional ingredients to potting soil, you can easily turn it into an incredible homemade seed starting soil. One that is ideal for quick germination – and healthy fast root growth!

How To Make The Perfect Homemade Seed Starting Soil

Although there are a few good seed starting soil mixes available commercially, they can be quite pricey. But by mixing together a good potting soil mix with 3 additional all-natural ingredients, you can make the best seed starting soil around – and for far less!

Three additives spilled on a table that should be added to potting soil to help improve drainage and make lighter soil.
Potting soil alone is a good start for growing seeds, but it needs a few additional ingredients in order to be light enough for seedlings to grow.

Even better, not only will making your own mix save you a bit of cash compared to store bought brands, it also allows you to create a 100% organic mix. That, of course, can be a great peace of mind when growing vegetable plants from seed.

With growing success in mind, here is a look at the 4 special ingredients needed to make perfect seed starting soil – and how to mix them together to get your seeds off to an incredible start!

#1) Potting Soil – How To Make Homemade Seed Starting Soil

A great seed starting soil all starts with potting soil. Potting soil is the perfect base for creating a rich, healthy seed starting soil mix.

Start by selecting a good all-purpose potting soil. Be sure that it does not include any fertilizers in the mix. Strong fertilizers can actually hurt young seedlings more than help. Young seedlings require a lighter, slow-release fertilizer to allow for even growth.

If too much fertilizer is present, at best, it will lead to plants with excessive early foliage growth but weak stems. Unfortunately, too much fertilizer is more likely to be fatal to young seedlings.

#2) Perlite – How To Make Homemade Seed Starting Soil

Perlite is an all-natural substance made from volcanic glass. When exposed to extremely high temperatures (1500+ degrees), perlite puffs into an airy, lightweight substance that looks quite similar to bits of white styrofoam. And it happens to be a perfect ingredient for making great seed starting soil!

Perlite lightens the soil weight tremendously, all while creating air channels in the soil for water and air. Both of these qualities are vital to strong seedling growth. It is exactly why you will see perlite as an ingredient in many potting soils as well.

perlite - volcanic glass
Many think the white, lightweight grains of perlite are made from styrofoam – they are actually puffed volcanic glass.

Perlite never breaks down, so it keeps the soil from compacting together permanently. Once you purchase a bag of perlite, it will stay good forever. And once it’s in the ground, it will also help forever as well! Affiliate Product Link : Espoma Perlite 8 qt. Bag

#3) Compost – How To Make Homemade Seed Starting Soil

Whenever you want to add loose, lightweight and fertile power to any soil, compost is the answer! It not only helps to lighten a homemade seed starting soil mix, it also improves the overall drainage of the soil as well.

Compost is overflowing with nutrients that are easily absorbed by tender roots. Even better, those nutrients are not overly strong, so they won’t overpower young seedlings. In addition, compost can hold in excess of 10 times its weight in moisture – which means it can help seedlings get the moisture they need to sprout and grow.

When adding compost to your seed starting mix, it’s important to use use ultra-fine compost. If using compost from your home pile, screen it first to remove any large chunks that may have not fully broken down yet.

Compost is one of the best ingredients you can add to seed starting soil.

This is one time where picking up a bag of compost can be helpful. Most commercial bags of compost have already been screened and are quite fine. Affiliate Link: Charlies Compost 10 Lb. Bag

#4) Worm Castings – How To Make Homemade Seed Starting Soil

The 4th and final ingredient to add to your mix is worm castings. Worm castings, which are the manure of worms, are the true hero of a perfect seed starting mix.

The light makeup of the castings helps to break up and lighten soil much like perlite – but with one big difference – worm castings are filled with loads of trace minerals and nutrients that can easily and quickly be absorbed by seedlings to power them up.

These nutrients slowly release over time and leach into the soil as they break down. Just like compost, worm castings also act as the ultimate slow-release fertilizer for young seedlings.

Although you could use just compost, perlite, and potting soil, worm castings take homemade potting soil to another level. One that will have your plants strong and healthy come transplant day! Product Link : 100% Pure Worm Castings

A cupful of worm castings that should be added to homemade seed starting soil.
Worm castings are light and airy but are still packed full of nutrients. They can easily absorb into the roots of young seedlings.

Creating The Mix – How To Make Homemade Seed Starting Soil

The best part of all in creating your own seed starting soil is how easy it is to mix together. To make, simply combine equal parts of each of the four ingredients above. It is usually best to premix all four in a large wheelbarrow or 5-gallon bucket and then fill your seed trays.

For best results, always water down your soil in the trays a few days prior to seed planting day. This will help to provide good moisture in the soil for better germination. It also allows the soil to settle in the containers, giving you time to top it off before planting seeds.

For more great information on starting seeds and how to provide them the right lighting for success, be sure to check out our article: The Best Lights To Use For Starting Seeds Indoors – Simple, Easy & Inexpensive!

Make this the year you create your own seed starting mix and grow your best plants ever!

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