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How To Make a Seed Starting Soil Mix

make a seed starting soil mixFor those looking to start their seeds, you may find a lot of different information about the proper soil to start seeds in. Of course, we’ve all seen the over-priced seed starting mixes at our local garden stores, but are they really necessary?

It turns out, they aren’t! There’s actually very little difference in the soil you will use to start your seeds and the soil your plants will grow in until they are harvested.

Making a Seed Starting Soil Mix

By using the below base, amendments and minerals for your seed starting soil mix, you will be well on your way to harvesting a bountiful crop of fruits and veggies.

Remember, you don’t necessarily need a seed starting mix though, your seeds and plants can get by just fine with our gardening soil mix found here too.


These ingredients will make up the base of your soil. You will notice there are much more aeration and peat moss in a seed starting mix than a regular garden mix. Since your seeds do not have developed root systems yet, the more aerated and drained the soil is kept while your seeds germinate, the better.

With the above inputs in mind, for each cubic foot of soil you intend to make, you will want to add in the following measurements:

  • 3.4 gallons of Sphagnum Peat Moss
  • 3.4 gallons of Aeration
  • 0.75 gallons of Compost

Additional Inputs:

For this, you will add the same inputs as we do for the regular gardening soil mix. Every cubic foot of soil you mix up, you will want to use roughly a ¼ cup of each of the below inputs.


Now, we will use almost the same minerals as we would with a regular gardening mix. For every cubic foot of soil, you will want to use a ½ cup of each of the below minerals.

Learn more about these additional inputs and minerals here.

What if I want to sow directly into my garden plot?

As mentioned earlier, it’s not totally necessary to mix up a seed starting mix, especially if you intend to directly sow your seeds into your garden plot. In fact, some plants should be directly sowed for best results, such as carrots, onion, potatoes, and many other root vegetables.

For this, you will just want to be sure your plot isn’t deficient in any essential nutrients. To do so, there are a few options for you:

  1. Pay for a soil test to tell you exactly what’s missing or locked up in your soil.
  2. Mix in some fresh compost to the plot. Then, mulch the plot. This should provide the nutrients needs for the upcoming growing season. Of course, if you notice any deficiencies presenting themselves throughout the growing cycle, simply add some amendments or compost to remedy the situation.