at my local seed and feed they carry greenhouse sized ammendments find a place like that i live in a small city so if live somewhere large shouldnt be an issue. they have 25kg bags of organic nutrients.. comes in green bags bio fert or something. anyway has a balanced 1005 organic omri formula which is great for a base. 4;3;5 or something along those lines. leondorite feathermeal bat guano bone meal pelletized. although best thing to do is get those cheapo tester caps. see what the soil needs and ammend from there. but as a base and ease of use 1 bag 46 bucks cant buy bone meal for much cheaper then that.
big believer in shrimp compost chitosan plus 50% more npk then sheep manure.
get large bags of diatomacious earth used for horses. may help keep some bugs out and adds few micros and silica if u are a beleiver. RAW sells small bags of silica but its just diatomacious earth 25kg bags are cheap.
alfalpha pellets are good. if can find organic prob wise. micros aminos organic material and of course alot of N.
horses are fed kelp meal aswell cheap source. slightly more salt perhaps then liguid formulas but think benefits outweigh any issue there. actual plant will def have more enzymes and promote beneficials. folks use kelp straight off the beach so should be fine.
health food stores sell bags of micronized kelp aswell, good for heavy sprayers that can handle littel grit.
coco coir is a great amendment
hope people move away from peat. just think about the trucks that move bulky peat from the northern tundra to cali every year. and it basically like burning coal as far as adding more carbon back to carbon cycle from being sequestered. and most places /greenhouses use once and burn.