My first comment. I love cherries and I want to eat all of these in one sitting until I feel deep regret. :)
Cherries are my absolute favorite. My aunt used to have a cherry tree when I was a kid and I loved picking em fresh. She died from brain cancer after a long battle. Love her so much still, one of the only family members who understood me growing up.
And how are they? Sweet? Do you need a fill blown tree for that? Or is sit something I can grow on a balcony?
A cherry tree can be a pretty big tree. I don't know how big your balcony is, but AFAIK cherry tree roots are about as wide as the crown so I would say no.
