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How To Create The Best Seed Starting Soil – From Just Four Simple Ingredients!

It’s plain and simple – to grow strong, healthy, vibrant vegetable and flower transplants from seed, you need to start with the best seed starting soil possible – and for us, there is no better way to do that than to make your own right at home with just four basic ingredients!

On our little farm, we start nearly all of our vegetable and flower plants from seed every year. Not only is it a great way to save on our gardening budget, it also allows us to try vegetables and flowers we can’t find locally.

When growing from seed, the only limit to what you grow is the ability to find a seed for it. And with all of the amazing specialty seed companies that exist today, you can almost find a seed for anything!

seed starting soil
When you grow your own plants from seed, it not only saves money, but allows you to grow so many more unique varieties than just the common ones found in most big box stores and local nurseries.

Growing from seed has allowed us the opportunity to grow all kinds of delicious heirloom tomatoes. Varieties like Tiger Blush, Big Rainbow and a slew of other incredible varieties fill our garden every year. And we just wouldn’t be able to find them if we didn’t grow them from seed!

The Advantages Of Growing Your Own Plants – How To Create The Best Seed Starting Soil

Starting our own plants from seed lets us control the growing process from start to finish. By filling our seed starting soil with powerful and rich organic ingredients, we all but ensure that with proper care, the seedlings will grow into incredibly strong and healthy transplants.

But here’s the best part of all, not only is making your own powerful seed starting soil quick and easy, it requires only four all-natural ingredients to create it. Ingredients that will have your seeds sprouting faster than ever. And even better, turning into transplants that are ready to grow fast when spring planting day arrives!

Creating The Perfect Seed Starting Soil

Up until about seven years ago, we created our seed starting soil from just three ingredients. potting soil, perlite and compost. It certainly performed well, but it wasn’t until we added worm castings into the mix that the soil began to help produce truly amazing results. (We include our seed starting soil recipe with worm castings near the end of the article.)

the power of worm castings
With the addition of worm castings to our seed starting mix, our plants took off like never before!

The difference in our plants with and without worm castings in the mix was unbelievable. In fact, to say it was a game changer would be the understatement of the year.

We talk about the advantages of using worm castings to power plants quite a bit on the blog. They are great for powering up hanging baskets and containers. Worm Castings can also be used as a slow release fertilizer.

They are perfect to help boost vegetable and flowers in gardens and flowerbeds with gentle power. They can even be soaked in water to make a wondrous fertilizing tea for plants.

But when it comes to using castings as a major ingredient in our seed starting soil, they are simply out of this world. With castings in the soil, our plants germinate faster. They grow thicker, larger and more rapidly as well. Affiliate Product Link : 100% Worm Castings

All it takes is one look at our transplant’s thick stems, dark green healthy foliage, and massive root base on planting day to see how well it works to power up our plants.

Why Worm Castings Help To Create Incredible Seedlings

Great seed starting soil needs to be light, airy, drain well, and be full of nutrients. But when it comes to those nutrients, it is how they are able to deliver their power to tender seedlings that makes all the difference.

fertilizing hanging baskets
Worm castings are wonderful when it comes to fertilizing all vegetables – from tiny seedlings, to fully mature plants!

Young seedlings that receive little to no nutrients simply struggle to survive. But seeds that receive too many nutrients too quickly have issues as well. The key is to strike the right balance in the middle.

Over-fertilized soil can result in top heavy growth but underdeveloped root systems. And that can spell big trouble for plants come transplanting time! So the key is a fertile soil that delivers slow, steady growth. And when it comes to worm castings, they absolutely rock at that process!

Even better, worm castings improve the soil’s structure and its ability to retain moisture as well. All of which are huge keys to growing strong, healthy transplants.

The Formula For Success

Although there are many commercial seed-starting mixes available with slow release fertilizers, making your own great organic seed starting mix at home is simple. If you do opt to purchase seed starting mix, still add in those worm castings! Mix in one cup for every three to four cups of seed starting soil to really power it up.

Our Seed Starting Mix

So what is the exact mix we use at the farm to create our own seed starting soil? For an amazingly fertile seed starting mix, we use this simple formula : 1 cup of potting soil, 1 cup of fine compost, 1 cup of worm castings and 1 cup of perlite. It really is that simple. And does it ever work like magic to grow amazing plants from seed!

Listen Below To Our Podcast On Starting Seeds Indoors!

Potting soil is loose and well draining. The compost is as well, but really energizes the soil with a great range of minerals and nutrients. The worm castings, as we have covered in depth, provide slow, steady nutrients and also help lighten the soil mix.

That leaves perlite as the fourth and final ingredient. Perlite also happens to be a big key for creating a great seed starting mix. Perlite lightens the soil tremendously with it’s airy make-up. And even better, perlite is 100 percent organic.

Sometimes, it is often confused as a styrofoam product due to its white little pebble-like appearance. The white substance forms when volcanic glass heats to a high temperature and then pops. The result is a light and airy organic popcorn-like substance perfect for lightening up soil and retaining moisture.

It is used in many commercial potting mixes for that very reason. And when used in seed starting soil, it allows the roots to easily grow without the soil being too hard or compacted. Here is to starting your seeds from scratch this year with the perfect seed starting soil mix! Happy Gardening – Jim and Mary

Jim and Mary Competti have been writing gardening, DIY and recipe articles and books for over 15 years from their 46 acre Ohio farm. The two are frequent speakers on all things gardening and love to travel in their spare time.

As always, feel free to email us at thefarm@owgarden.com with comments, questions, or to simply say hello! You can sign up for our free email list in the subscribe now box in the middle of this article. Follow us on Facebook here : OWG Facebook. This article may contain affiliate links.