1104 Syringa of flowering plants, Syringa (philadelphus; lilac). It belongs to the Oleaceae family. The "Syringa" most common member species is the Syringa vulgaris (common lilac). The official naming citation was mentioned in "The Names of the Minor Planets" by Paul Herget in 1955 (). Due to his many discoveries, Karl Reinmuth submitted a large list of 66 newly named asteroids in the early 1930s. The list covered his discoveries with numbers between and . This list also contained a sequence of 28 asteroids, starting with 1054 Forsytia, that were all named after plants, in particular flowering plants "(also see list of
1104 Syringa Calvin–Rehoboth Observatory in New Mexico, United States. Lightcurve analysis gave a well-defined rotation period of 5.1547 hours with a brightness amplitude of 0.27 magnitude (). According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's WISE telescope, "Syringa" measures between 19.711 and 24.30 kilometers in diameter and its surface has a low albedo between 0.031 and 0.045. The "Collaborative Asteroid Lightcurve Link" derives an albedo of 0.0434 and a diameter of 22.13 kilometers based on an absolute magnitude of 12.3. This minor planet was named after the genus