Petasites hybridus

Common butterbur is native to eastern and south-eastern Europe and western Asia. It was introduced to western Europe as a medicinal plant in the Middle Ages at the latest, and very early to Finland, as it was cultivated in the Academy’s garden in the 1670s (Tillandz 1683). Today, recorded findings range from southern Finland to Oulu and Rovaniemi in the north. It grows as a relict or escapee on ditch banks, shores, field and road banks, parks and wasteland. It migrates to new habitats as rhizome fragments in transported soil or garden waste, for example. The species is common as an ornamental.Japanese butterbur is native to eastern Asia. In its native range, it is among the first plants to settle on riversides and, for instance, volcanic ash fields. The plant was introduced to Finland as an ornamental. It grows as an escapee or relict in nutrient-rich shore forests, and on shores and field and road banks.

Common butterbur is also classified as invasive in Sweden, Norway, Denmark, Estonia, Latvia and Lithuania, while Japanese butterbur is classified as invasive in Norway and Denmark.