It says on the bag that it's peat moss, pine bark, vermiculite and perlite
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You probably want around 5-20% aeration by volume. That gives you the amount of vermiculite and perlite. I personally use the lava rocks for BBQs. Peat moss was 50% so that leaves 45-30% 1 inch pine bark mulch
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Typically what I do is put in some cheap potting mix, put the new plant on top of this so that it's at the right height. Then add in some lava rocks around it, will in some composted sheep or cow manure, add a few more rocks then top off with regular cheap compost. I'll leave a big gap at the top and then add in at least an inch of thicker pine bark
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After watering it in and waiting a few days I'll add in some worms and they will do the mixing and aeration for me. Mixing everything yourself is boring and messy, and the worms do a good enough job even if they eventually die out confined to a pot
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Adding leaf litter / more wood chips will keep it fertilised forever as long as you have worms in there alive.