How to Make your Own Vegetable Seed Starting Soil

If you want to ensure that the vegetables you grow are the healthiest they can be, then you must be involved in the growth of your vegetables from the start and that means growing them directly from vegetable seeds as opposed to buying established vegetable plants.

Now that is not to say that the vegetable plants you buy from your local garden nursery or home center are bad. It simply means when you start your vegetable plants at home from vegetable seeds you are in complete control of the environment in which your vegetable seeds will germinate and where they will grow.

This is important, because when you start directly from vegetable seeds, you get to choose the vegetable seed starting soil. The better the vegetable seed starting soil, the better the start will be for your vegetable plants, and in turn the healthier they can become.

Just like a tall skyscraper needs an excellent foundation, so do your vegetable plants. This foundation is your vegetable seed starting soil. The best vegetable seed starting soil you can have is one that actually contains no soil at all. Instead your vegetable seed starting soil is made up of three different ingredients.

Whether you make your own vegetable seed starting soil or buy commercially packaged vegetable seed starting soil, all should have these three main ingredients. Each of these three ingredients serves a purpose that helps your vegetable seeds germinate.

What you should be looking for in your vegetable seed starting soil is an ingredient that helps with water absorption so that you do not over water. That usually comes in the form of perlite or vermiculite. Both readily available at any garden center in its own form and will also be included in many commercial vegetable seed starting soils.

The second ingredient that should be on your radar is something that will make your vegetable seed starting soil loose and friable. Two good choices are sphagnum moss aka peat, or coir, which is the fiber extracted from the husks of coconuts. Both can be found at local home and garden centers or online.

Finally, your vegetable seed starting soil must contain some form of fertilizer otherwise the vegetable seed will not get the nutrients needed for proper germination. There are a wide variety of choices and combinations here, but the simplest vegetable seed starting fertilizer you will find is compost. Easily made at home, you can add in your own compost to your vegetable seed starting soil, which gives you a true, self made vegetable seed starting soil.

So how do you make your own vegetable seed starting soil with the items mentioned above? Making your own vegetable seed starting soil is very simple. Combine equal parts of all three ingredients, that is one part perlite or vermiculite, one part peat or coir, and one part compost, then mix them together.

Your homemade vegetable seed starting soil has everything your vegetable seeds need to germinate properly.

As mentioned earlier, you can also purchase vegetable seed starting soil from your local home or garden center. There a variety of different combinations of ingredients that are used with commercial vegetable seed starting soils, so be sure to read the packaging to know exactly what you are buying. Some are formulated for specific vegetable varieties, such as tomato or pepper mixes, make sure you read the bag before you buy.

Grow Tomatoes from Seed

Tomato Seeds Marglobe variety

Tomatoes are the number one item grown in the home vegetable garden.  And while many people will still and always refer to the tomato as a vegetable the tomato is botanically a fruit. 

Tomatoes are also one of the easiest fruits to grow in the home vegetable garden.  With the wide range of tomato varieties to choose from, you are sure to find the right tomato plant for your specific climate.

How you specifically use your tomato for consumption may also steer you into the direction of which tomato variety you will grow.  For instance, I find using home grown Roma tomatoes are the most ideal to make tomato based sauces and tomato based salsas.  The main reason being, besides the great taste Roma tomatoes have, is the fact that it is easier to remove the seeds from Roma tomatoes.

Now that is not to say that other varieties of tomatoes such as cherry, pear or beefsteak tomatoes would not serve the same purpose for a recipe.  From my own experience, removing tomato seeds can be time consuming in varieties not named Roma.  I will save the beefsteak tomatoes for my summer lunchtime sandwich with mayo and cherry tomatoes for salads.

Regardless of which tomato variety you choose, I believe that you will not find anything more rewarding in your garden, especially for your tomato crop, than growing all of those tasty tomatoes from seeds.  Something about the challenge of growing tomatoes directly from the seed, starting your tomato plants indoors before you can even move the tomato plants to the outdoors, strikes me (and maybe you) as one of those tasks where you say, “Yeah, I did it, I grew those tomatoes from seeds”.

Here is what I do, to maximize the success of my tomato plants, and of course yield nice juicy tomatoes for all of those tomato recipe items I mentioned earlier.

As with other seeds, you won’t have much luck in the germination process with your tomato seeds if you start with a terrible starter soil.  Here is where you have plenty of options to start your tomato seeds in.  You have the expandable peat pellets.  These are small hard and compressed starter pellets that you add hot water to and they expand.  I use these quite often to start my tomato seeds and do very well with them.  Using the peat pellets, I easily get about 95% to 97% germination rates of my tomato seeds. Of course I also use them in conjunction with a propagation dome. 

Along with peat pellets, you can start your tomato seeds in a pre-packaged starter soil that you can purchase at any home or garden center.  These starter soils are especially formulated for seed starting.  They now even make starter soils for tomato seeds.  Tomato seed starting soil includes specific nutrients that not only increase germination rates, but help build strong roots of the young tomato plants, when the tomato plants need it the most.

You can also make your own tomato seed starting soil with many recipes found by doing a quick Google search.  Tomato seed starting soil recipes are plenty in abundance online.  You are sure to find a tomato seed starting soil that meets your climate and zone requirements.

Under optimal growing conditions, and that means, your tomato seed starters are getting at least 6 hours of sunlight per day, are in a propagation dome (or something similar), and the soil is moist but not saturated, you can expect your tomato seeds to germinate in as little as 6 days.  If you do not see any activity out of your tomato seeds after day 10, something has gone wrong, and you may have to start over.

Tomatoes love to grow in climates that are hot and humid, which explains why we here in New Jersey do so well with growing tomatoes.  Even in the worse of years with drought, our tomatoes in New Jersey seem to produce above average.  With that said, do not transplant your tomato starters too soon.  If the threat of frost is still at a medium to high level in your area, keep your tomato seed starters indoors until fear of frost passes by.  A single night’s worth of frost will decimate your tomato seed starters.  You can always cover them at night with a cloche or a 6 mil thick clear plastic tarp, but I like to leave my tomato seed starters indoors until the time comes to move them.

I won’t get into too much detail regarding hardening off your tomato plants in this article and podcast series.  As a quick overview, hardening off your tomato plants simply means to get them used to the outdoors so as not to shock your tomato plants when you do make the move.

When planting your tomato starters outdoors, choose a location that receives a full day’s worth of sun and try not to plant your tomato plants in an area where you previously planted potatoes, peppers or eggplants. 

When it comes to spacing out your tomato plants, I have read a thousand different sizes that will work for hundreds of different tomato varieties.  For me, I like to prop up my tomato plants with tomato cages.  They cost a couple of bucks a piece from the local home center and are virtually maintenance free.  Getting back to tomato spacing, I use the measurement of the diameter of the tomato cage top and add 6 inches.  It is this measurement that I use to space out my tomato plants.  This method has worked out well for me for the better part of 30 years.

Some people like to use tomato stakes and other methods to support their tomato plants and all I am sure they are all fine.  In fact my dad used me and my brother’s old hockey sticks when we were kids to use as stakes for his tomato plants.  You are only limited by your imagination.  However, when in doubt, space out your tomato plants no less than fifteen inches, and even at that spacing, that will be tight.

As a side note, yes those Topsy Turvey™ upside down tomato planters really do work and produce a lot of tomatoes.  So if you are limited on space, it may be a good way for you to go.  You can also make your own upside down tomato growers out of some 5 gallon buckets, but I will save that for a future discussion.

Now that you have your tomatoes started, transplanted and supported, let’s talk about simple care.  While your tomato plants are growing give them a good watering making sure the soil your tomatoes are planted in remains moist but not saturated.  Once you begin to harvest your tomatoes you can reduce your watering, unless of course conditions are very dry.

Tomatoes required high amounts of nutrients, especially Nitrogen, Potassium and Phosphorous.  Be sure to add these as the season goes on.  Again there are plenty of choices for your tomato plants, from organic, to Miracle Gro™ and tomato specific formulas.   Me personally, I create loads of compost and will continually add this to the base of my tomato plants throughout the course of my gardening season. 

Good luck with your tomato crop for many seasons to come!

About the Author 
 Mike Podlesny is the author of Vegetable Gardening for the Average Person: A Guide to Vegetable Gardening for the rest of us. Be sure to join Mike`s vegetable seeds mailing list.

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