Greenhouse grow help

Hey, guys, I plan to start growing an autoflower strain in my greenhouse this season, in a pot. I was needing some help with choosing the correct fertilizers and soils.

I already have some basic knowledge, because i did a quite a bit of research into growing but mostly into hydroponics and indoor growing, but then realized that it would be too expensive to go hydro and buy name-brand fertilizers. I live in the Baltic region of Europe and I don’t have any growshops in my country, nor the surrounding countries, so I dont have acces to any name-brand fertilizers or soils, like foxfarm. Importing the needed stuff costs alot, especially the shipping. I need help choosing the best soil mix and fertilizers. I don’t own any pH meters or EC meters, but I can get universal pH testing strips, so is it possible to somehow test the soil using the strips.

For the substrate, I have acces to coco coir, some universal potting soils, peat, vermiculite, perlite, worm castings. I dont have access to bone meal and peat moss.

For fertilizers it’s even worse. I cant get any like grow, bloom, micro type stuff, except for orchids. I can get some fertilizers with exact NPK values and only some information on the other elements. I also have acces to some universal fertilizers with no info on the NPK or other stuff. And I don’t dont really want to mix my own fertilizers.
I was wondering what would be the best soil “recipe”.

And also if I really should be stressing over the NPK values and how important are the other elements. Would universal tomato or other vegetable fertilizers work. And when and how much should I give my plants.

Can I survive with only universal testing strips?

Also any tips on greenhouse growing?

This is my first time on the growing scene, and my first time on this forum. I hope I don’t come off lazy or stupid, because im ready to devote a lot of time into this stuff and I’m really passionate for it. I already have devoted a considerable time into research and I’m ready to devote more! All help is appreciated, thanks!

Tomato ferts will work. Mix your have access to list together w some compost and in your area perhaps you can find organic ferts. If synthetics are unobtainable. Sounds like ocean products should be available to you. Shell,seaweed,fish emulsions etc build and maintain your soil if you cant get imo overly priced,easy to screw up synthetics but everyones diff.

If you can grow a tomato plant with what you can get ,your all set. Its really only as scientific and complicated as you want to make it.

Perlite, Epsom salts, worm castings ,composted manure, lime, universal potting will get you a basic mix in time for planting.
Good enough to get you going, plus the tomato ferts. That usually has more lime added than general vegetable NPK pellets.

Probably need more than 30 days to get a good batch of local super soil going, adding too much now won't be beneficial.
Sometimes a bag of rabbit feed, or horse feed will have some great ingredients for super soil. Alfalfa, seaweed, grains all in a pellet.