We've had this conversation before already, TV:
https://www.helpfulgardener.com/forum/vi ... 77#p370577
You cannot grow stuff in pure peat moss. It is sterile, without nutrients, very acidic, holds on to water like crazy, then dries out and sucks water away from your plants and cannot be easily re-wetted.
And just pouring fertilizer on it does not help and trying to find other chemicals to add on to it does not help. You have to find a way to get something to mix it with that improves its texture, aeration, drainage, etc. Your sandy backyard soil would help, as has been mentioned. Compost would help a lot. Definitely you should be starting a backyard compost pile or a worm bin or something. But that takes a long time for any finished results. Maybe in the meantime, you have a friend who composts who could give you enough to help with a few containers? Decomposed granite, crushed lava rock and other mineral construction materials would help.
Surely there are other gardeners around you whom you could talk to about these issues, find out what they do. Are you in/ near a city?