2022 was the first year in which I put quite a lot, maybe 100, seedlings, sections and young plants in pots.
In substrate with mostly mixed grain lava, similar to Carsten, placed in full shade.
They are always kept slightly moist.
After a few weeks, the first leaves turned pale, so I fertilized some liquid over the foliage.
Now they got darker, many even to a bronze hue, is that normal?
Since I constantly water the leaves, I have a lot of leaf stains, next time I would plan a flood tank.
The very dry ones in the garden, but shady, on the other hand, are spotless.
All in the pot are due to be released into the open soon, but for some that won't be until 2023...