fastigate
/fæstɪˈɡeɪt/Definitions
1. verb
to train or grow a tree or shrub in a way that it grows against a wall or other support
“The gardener decided to fastigate the vines so they would have more space in the garden.”
2. noun
a tree or shrub trained or grown in this way
“The garden features many fastigates, adding beauty and structure to the space.”