Pergola vs arbor vs trellis: what's the difference?
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The short answer: a trellis is a flat lattice panel that supports climbing plants. An arbor is a small freestanding archway, often with trellis sides, that frames a path, gate or bench. A pergola is the largest of the three: a roofed framework of posts, beams and rafters that covers a whole patio or seating area.
Side-by-side comparison
| Feature | Trellis | Arbor | Pergola |
|---|---|---|---|
| What it is | A flat lattice or grid panel | A small archway or frame with an open top | Posts, beams and open rafters over an area |
| Size | Smallest | Medium: about as wide as a path | Largest: covers a room-sized space |
| Main job | Support climbing plants | Frame an entrance or focal point | Create shade and an outdoor room |
| Stands alone? | Freestanding or fixed to a wall or fence | Freestanding | Freestanding or attached to the house |
| Shade | Little | A small patch | Partial shade over a seating area |
| Typical spot | Walls, fences, raised beds | Garden paths, gates, over a bench | Patios, decks, outdoor kitchens, hot tubs |
| Relative cost | Lowest | Low to medium | Highest |
What is a trellis?
A trellis is an open grid of wood, metal, vinyl or wire that gives climbing plants something to grip. It is usually a flat panel, either fixed to a wall or fence or set into the ground on its own legs. Trellises are also used as light privacy screens and to hide things like air-conditioning units or trash cans.
Choose a trellis when you want vertical growing space or a green screen without building a structure.
What is an arbor?
An arbor is a small freestanding structure with two sides and an open top, often arched, that you walk through or sit under. The sides are frequently trellis panels, so plants can grow up and over. Arbors are typically placed over a garden path, at a gate, at the entrance to a vegetable garden or over a bench to create a shaded seat.
Choose an arbor when you want a focal point or a sense of entrance, rather than a space to sit in.
What is a pergola?
A pergola is a larger structure of posts supporting beams and a grid of open rafters. It is big enough to cover furniture, so it creates an outdoor room on a patio or deck. A pergola can stand alone or attach to the house, and it can be upgraded later with a canopy, louvered roof or panels. If you want full rain cover, compare it with a gazebo in our pergola vs gazebo guide.
Which one do you need?
- "I want to grow climbers up a wall or fence." A trellis.
- "I want a pretty entrance to the garden or a shaded bench." An arbor.
- "I want shade over a table, seating area or hot tub." A pergola.
- "I want to stay dry when it rains." None of these on their own: look at a gazebo, or a pergola with a roof or canopy.
Using them together
The three work well as a family. A landscape designer might put a pergola over the patio, trellis panels between two of its posts for privacy, and an arbor where the patio path meets the lawn, all in the same material and color so the yard reads as one design. Keeping the post size and finish consistent is what ties them together.
Next steps
- Need weather cover? Read pergola vs gazebo.
- Planning where it goes? Start with backyard planning.
- Browse all pergola and gazebo guides.
Common questions
Is an arbor the same as a pergola?
No. Both have posts and an open top, but an arbor is much smaller and usually frames a path, gate or bench, while a pergola is big enough to cover a seating or dining area.
What is the difference between an arbor and an arbour?
Nothing but spelling. Arbor is the American spelling and arbour is the British spelling of the same garden structure.
Can you attach a trellis to a pergola?
Yes. Trellis panels fixed between pergola posts are a common way to add privacy, block low sun from one side and give climbing plants a route up to the roof.
Which is cheapest: a pergola, arbor or trellis?
A trellis is the least expensive because it is a single panel. An arbor costs more, and a pergola costs the most because it is the largest structure with the most material and the biggest foundations.
What plants grow best on an arbor or pergola?
Vigorous climbers such as wisteria, grapes, climbing roses, clematis and climbing hydrangea suit pergolas and arbors. Heavy woody climbers like wisteria need a strong structure, so check that a kit is sturdy enough before planting them.