If you garden indoors on any real scale you most likely have experience with a soilless mix. Soilless mixtures are a term commonly given to a mix including one or more of the following peat moss, coconut fiber coir, perlite, vermiculite, fertilizer mycorrhiza.
one of the most common name brands of these mixes are “Sunshine” and they have many different versions most given a number designation 1, 2, 3, 4 and so on each slightly different. Number 4 is the most common and used by most people. Number 4 consists of peat moss, extra perlite, fertilizer for about 1 week for seedlings, and a wetting agent.
Wetting agent: An often overlooked and common ingredient in peat moss soilless mixes is the wetting agent it is crucial and its the ingredient that makes gardening with peat moss possible and not a nightmare.
For our intents and purposes the dish soap in the recipe will be the wetting agent it acts as a surfactant and helps spread the water over the peat moss. Without it the peat hates water you can put it on a garden or in a pot and water and water it seems like its wetting but if you dig just below the surface it’s drier than a popcorn fart. It is very deceiving because there top looks wet. So the soap or other such wetting agent is key and once you understand this you wont go back to pre made bails of soilless you are saving a case of cold ones each time that’s the canadian way.
These mixes are pricey and get more and more so every year prompting a lot of people to seek alternatives or to make their own mixes. In the BC area of canada a 3.8 cubic foot bag of sunshine or Promix etc will set you back a little under $30 at the time I’m writing this. while a 3.8 cubic foot bag of straight peat moss is under $9.00.
Thats a massive difference, the other ingredients do not make up the difference in fact for the cost of those ingredients you can usually make 3 times the quantity of soilless.
Make your own Sunshine #4 you will need
1 bag of Peat Moss
1 bag of perlite 4cu ft
liquid dish soap (no bleach)
Thats is in a large container put in your peat moss and break it up it comes dry and compressed into a semi solid brick. Once its is broken up take your dish soap out and drizzle a fine bead over the top (you can always add more)
now add water a gallon at a time and use a small gardner rake or your hands to mix it up and into the peat moss for first few gallons ont make much of a noticeable difference as the peat moss is dry and sheds water not mixed with the soap as it starts to change little balls will form in the peat moss. Once you get to the point where the peat had balled up stop adding water and now mix until all those radish sized balls bust up and you should end up with the perfect moisture content. If you end up with too wet do not worry the wettest will fall to the bottom as you mix and you can use the mix from the top down until the excess water evaporates away
You can now add your perlite start with large scoops and you will use about a 1/4 of a 4cu ft bag maybe a little more for each 3.8cu ft bag of peat moss. The perlite is the ingredient that keeps the mix airy helps prevent damage from over watering so you can always have a little too much it won’t hurt a lot too much may require you to water the plants more often.
That’s it you have now made your own sunshine mix as for the fertilizer follow the directions on the label it’s a safer than my telling you to use x as you might be using a different product organic or time release fertilizer so….. regardless most people have a fert that they water in and the fert in the mix will just get in the way, itr is more for people starting seedlings not for people repotting or growing bigger plants.
Pro-Tip: This also works with coconut coir with only maybe a little less dish soap, coir holds more water to start off.
The other ingredients are up to you, most like a myco product some prefer to remain organic others want more airiration perlite or vermiculite that’s the only difference in the Numbers #4 extra perlite #2 no fertilizer, #1 basic regular perlite, and so on Promix is basically #4 which is the most commonly used and just buy a myco product to add it