The horse chestnut is a handsome flowering tree which can be grown in favourable spots in the south of Finland. When young, it is tender to autumn frosts and winter damage, which is why plants are usually imported from elsewhere. Hardiness improves with age.
The horse chestnut can best be described in a single word: big! In temperate climates it can achieve heights up to 30m. In Finland it only achieves about half this size, but develops a broad crown. Branches are sturdy and in winter have impressively large, sticky buds. In spring they produce large finger-lobed leaves and showy white flowers. In autumn the fruit is a large shiny brown nut covered in a spiky shell. The nuts are not edible by humans, but squirrels eat them.
At Arboretum Mustila the Balkan horse chestnuts have not grown as well as its American relatives, and there is not a single large specimen. The Arboretum collects seeds from Kouvola from a group of exceptionally large and hardy trees.