The garden is real pretty. Take whatever local expectations you have for some nice looking greenery, and crank it to eleven. They've got a whole hedge-maze, all meticulously clipped and shaped. Numerous types of flowers, likely taken and replanted from all across Equestria, sit pretty in bright splashes of colorful display, designed to draw the eye against the green backdrop. They've even got a marble fountain, styled with an Alicorn atop it that doesn't look quite like either Celestia or Luna. Hard to capture their specifics without color, I suppose. A lot of the art in the castle had the habit of giving them the same body shape, when Luna was a good head under Tia at this point.