Pergolas and trellises are perfect accent pieces for your back yard or garden area. A pergola is an archway-style framework that is great for providing shade for a seating area or hot tub, and a trellis is a barred-framework, typically put against walls to add a touch of personality. Both trellises and pergolas are typically used as a support for climbing plants like roses, ivy, morning glories, wisteria and hydrangeas.