Blida's nickname — Ouarda, "the Rose" — comes from the rose gardens that have surrounded the city since the Ottoman period. The Mitidja plain north and west of the city was once entirely given over to roses, orange groves, jasmine, and other aromatic plants grown for the production of essences, attars, and the famous eau de fleur d'oranger used in Algerian cooking.
Many of the gardens have been built over in the last century but pockets survive on the city's edge, particularly to the north toward Ouled Yaïch. The roses flower in April and May; the orange blossom comes earlier, in March. The local market on Saturdays still sells bottled rose-water and orange-flower water from the surviving distilleries — a cheap and useful souvenir.