Gardens are environment buildings in Tropico 5.
They come in 2 sizes, Small and Large. Small Gardens cost $160, and Large Gardens cost $400.
Both of the sizes have various styles, including Trees, Flower arrangements or ponds, Small gardens take either a 1x1 or 1x2 space, large gardens can take 2x2, 3x2, 3x3 or 4x2 space.
Building Gardens has no downsides and will improve the beauty of a location, as well as improve relations with Environmentalists.