Further info:I am finding trouble evolving my budew because it has to have max happiness at night to evolve
I got it at level 10 and made it to level 54 in the secret base which does not have night time. If anybody could help I would appreciate it.
Set your clock time to around midnight (to be sure) and level it up afterwards, it should evolve if it has max happiness. If you are not sure about the max happiness, feed D.Budew EV-reducing berries till it won’t have any effect first.