Oh man! You're all so kind. Thank you my friends! There's a second tree video online that I marked with "HO-scale" but the technique works just as good for taller trees. It's a one hour build, really quick and easy to put together and still looks good.
https://www.youtube.com/watch?v=QdJ9u9JvP7U&t=88s
I'll use exactly that tree on my layout, of course. The latex-bark-method works so well and the ready to use foliage by Dioramapersepe speeds up the whole process a lot. Ground Coffee straight from the pack was used so I called it "The Coffee Tree".
Cheers, Sarah