I would roughly add (per 10L soil):
- Worm castings ~ 1–2 L
- Manure pellets ~half a cup
- Dolomite lime ~ 1-2 tbsp
- Mycorrhizae
Rock dust (basalt or glacial) ~ 1-2 tbsp
Optional: kelp or wood ash (tiny amount) if you need more readily available K
Depending on the structure clay pebbles/perlite, as wanted/needed. No guarantee. 😋