This might be a lonnnng rant (or not since I don't like to stretch things unnecessarily) so you might want to buckle up.
The book is based on a protagonist who decides to write about potatoes and wants to find out what "Roter Baum" is. The book is based on "Zeit nach der Wiedervereinigung", that is after the unification of Germany and shows how the "then DDR" has changed after the unification.
But that's not where I started losing my interest. It's the constant unnecessary talks and long details of anything small and the personalities of the people he met, all those problems that poor guy faced and for what? To write about potatoes and find out what "Roter Baum" is.
The plot could've been so much different than making it entirely about potatoes. Personally, it kinda felt like the changes "nach der Wende" went completely in the background, felt more forced.
I still find it difficult how the book is named "Johannisnacht".
Also after 200 pages of reading, I at least anticipated Roter Baum must have been something interesting since he had an adventure of 200 pages but what is it? A Gasthof.
Now moving to the writing style. No inverted commas to indicate dialogues. I don't want to do a brainstorming and keep a check on who's saying what every next line. I DID THAT ENOUGH TRYING TO FIGURE OUT ABOUT ROTER BAUM AND POTATOES. The least that one can do is add inverted commas for DIALOGUES!
Coming to the humour part, I don't know if my humour is broken or the humour was really not humorous. Reading that entire thing with a blank face and then being asked "have found the joke?" by the prof., like no I didn't, tell me 'cause I don't find anything even mildly funny here.
The book felt entirely slow paced. Had this as a part of our lesson, and never again. Tried giving it a read again at home, and never ever again.
If the author wanted to show the changes after the Wiedervereinigung, it could've been done in so many better ways. And trust me, as a Germanistik Student, I've gone through the history of Germany every semester, so I know when I see it.
I'll add some more, if I'm in the mood but for now, that's all I guess since I've to go and finish an assignment based on the 5th chapter of this novel. I hope I don't fall asleep while reading. Again.