I don't know the name of this tree. Small purple plums. 2019 I had a bumper crop but this year three were only a very few on the tree and I didn't even pick them. Just let the birds dine. I wonder if it was because 2020 was the worst year of my life and maybe the tree picked up on corona virus et al and just said the heck with it and no one gets any plums. What should I be doing with the tree? Prune or not to prune? What fertilizer? Water how often. I didn't change anything I was doing from 2019 to 2020.