There are a number of trees in the garden, I guess in an attempt to "preserve the species". If the garden was larger, one could easily picture the House (and its garden) from a "House with a Garden" to Noeh's Kivotos (plants and not animals - it still puzzles me how come the plants survived the "hurricane" back then...).
Most of the plants, even if useful, are used for decoration purposes only. Excluding of course the Mournies, which consistently feed with their leaves the animals of the "garden-keeper" (a neighbor who's usually allowed entrance to the garden to take care of it during winter time) and the Tzitzifia (of course) who stands as a "symbol", at the edge of the garden, giving a Name to the village itself and failing to "grow up" over the years.