Having plants on the roof of vinyl pergola kits add beauty and greenery, but only certain varieties pf plants are more suited for pergolas. Typically climbing plants are favored in particular. Grapes are functional too, since plucking and tasting grapes as you walk though the walkway of a pergola is a fun and unique experience. It is advisable to remove all the lower growth as the grape vines develop and regular pruning and trimming of the plants gives a neat, clean look to the pergola. Grape vines also give much needed shade in summer, but allow sunlight in during winter.