Ornamental plants as aliens in Bulgaria
Hemerocallis fulva (Asphodelaceae) is an herbaceous perennial species native to Asia (China and Korean peninsula). The species is reported as naturalised in Asia, Australia, the EPPO region and North America (recorded as invasive in many states). Where the species is invasive, dense stands can form displacing native plants. In Bulgaria, it is widely cultivated as it is a robust garden ornamental which can withstand a wide range of environmental conditions. Over the last ten years H. fulva has been recorded as an escaped garden ornamental in eight floristic regions (Northeast Bulgaria, Forebalkan, Zneploe, Sofia, Vitosha, River Mesta, Rhodopi mountains west and central and Thracian lowland region) throughout Bulgaria where it occurs in urban and semi-urban environments, along roadsides, riverbanks and grassland. The populations consist of one to several dense areas that cover one to more than 100 m². H. fulva spreads vegetatively, as cultivated plants are sterile.
Oxalis articulata (Oxalidaceae) is a rhizomatous herbaceous perennial species native to South America (Argentina, Brazil, Paraguay and Uruguay). It is naturalised in many parts of the world with a temperate or Mediterranean climate including Europe, Australia, North America, Africa and Asia. In Bulgaria O. articulata is recorded in three floristic regions (Black Sea coast, Sofia, river Struma) where it grows in urban and semi-urban environments. Near the river Struma, the species grows in a natural habitat where 3 small groups of 3-7 plants grow in scrubland. O. articulata is not a common ornamental plant in Bulgaria but it can be found as a pot or balcony plant grown outside in the warmer summer months.
Sources
Petrova A, Vladimirov V (2019) Reports of some ornamental plants as aliens for the Bulgarian flora. Phytologia Balcanica 25, 387-394.