From Tardis Wiki, the free Doctor Who reference

A garden was a space for the growing and displaying of plants and flowers.

The Third Doctor and Sarah Jane Smith met St. Nicholas in the garden of a New York City mansion. (PROSE: A Visit from Saint Nicholas)

A group of peaceful Sontarans who had crashed on the Moon once took up gardening. Their gardens reminded Abby of the Zen gardens on New Japan. (AUDIO: The Moonrakers)

As Mickey Smith claimed Rose Tyler told him, the Ninth Doctor once landed the TARDIS in a big yellow garden full of balloons. (TV: The Christmas Invasion)

At Easter, the newly regenerated Eleventh Doctor crashed his TARDIS in Amy Pond's back garden in Leadworth. (TV: The Eleventh Hour)

Entertainment features at the Two Streams Facility included a garden. (TV: The Girl Who Waited)

Maria Jackson saw Sarah Jane Smith with a Star Poet in her garden. This was the first alien Maria ever saw. (TV: Invasion of the Bane)

Kent was known as "the garden of England". (AUDIO: The Mouthless Dead; PROSE: Transit)

By 200,100, Earth had become a much harsher place. No one could go outside or grow a garden. (TV: Bad Wolf)