"The garden is there."
It is acceptable, but sounds very philosophical (e.g. Любов є страдання = Love is suffering ) or dictionary-like (Школа є місце, де... = School is a place where...)
Also because "є" means "to have" in 90% of the cases. We very often use a reflexive way of saying "I have":
1) (direct) Я маю кота (literally: "I have cat" = I have a cat)
2) (reflexive) У мене є кіт (literally: "At me is a cat" = I have a cat) - more spoken
So if you say Сад є там or even Там є сад it sounds more like "There is a garden there" than "The garden is there".