I'm a little confused as to why you don't want fertilizer. Plants need some type of fertilizer to grow. Perhaps you mean you don't want artificially made chemical fertilizer?
What I use regardless of it's a houseplant or a bioactive enclosure with animals is worm castings, fish water, and the old substrate from my roach and mealworm bins, and other compost I've made, and then combine a small amount of that with cocopeat and vermiculite or perlite. Something like 10-20% fertilizer depending on the type, 20% perlite/vermiculte, and the rest cocopeat. I get cocopeat in a HUGE brick from Amazon because it's the cheapest source for me, and the rest of the stuff can be found at Home Depot or Lowes. You can find cocopeat at Home Depot or Lowes, and if you only need a small amount, that's probably the more economical route for you.
If you really want NO fertilizer at all, cocopeat + perlite/vermiculte will accomplish that, but it probably won't sustain plant growth very long.
Reply With Quote