The Japanese tree lilac is very different from other lilac (Syringa) species. Even in Finland it is distinctly tree-like, and in its native habitat can reach 20m (65 ft). It also flowers later than the other lilacs, usually late June or even July, with creamy clusters of fragrant flowers up to 30 cms. (1ft.)
Tree lilacs occur in many forms usually divided into two subspecies, the more continental Amur (or Manchurian) lilacs (subsp. amurensis) of the Asian mainland, and the more maritime Japanese tree lilacs of Japan and Sakhalin Island (subsp. reticulata). Differences are very slight, and northern provenances of both subspecies grow successfully in Finland as far north as Oulu.
At Mustila, the first two specimens were planted in 1914. Neither tree has survived, but there are more recent plantings in several places. The best specimen can be found on Ketunmäki (or Fox Hill) near Juhlapaikka (or Festival Area)rising high above the other lilacs in the area.