Istanbul's art scene is mushrooming, aided by the recent openings of nonprofit art spaces like Garanti Bank's Salt, Vehbi Koç Foundation's Arter-Space for Art and Borusan Holding's ArtCenter Istanbul. Their arrival may give a boost to a longtime also-ran in the art-biennial pack—the Istanbul Biennial, an exhibition of contemporary art that opens Saturday and runs through Nov. 13 at the Antrepo warehouses.

Biennials typically serve as breakout moments for hot young artists,...