Here are examples of non-native plants introduced to the UK from specific countries or regions with a known introduction:
Americas (North & South):
Canada: Canadian pondweed (Elodea canadensis)
USA: American skunk-cabbage (Lysichiton americanus)
South America (Chile): Chilean rhubarb (Gunnera tinctoria), also known as giant rhubarb
Asia:
Japan: Japanese knotweed (Fallopia japonica)
Himalayas (region covering parts of Nepal, India, etc.):Himalayan balsam (Impatiens glandulifera)
China: Butterfly bush (Buddleja davidii)
Europe:
Spain: Spanish bluebell (Hyacinthoides hispanica), which hybridises with the native bluebell
Norway (via wider Europe): Sycamore (Acer pseudoplatanus), naturalised in the UK, introduced from continental Europe
Africa/Australasia:
New Zealand: Hebe (Hebe spp.), common in UK gardens
Australia: Australian swamp stonecrop (Crassula helmsii)
South Africa: Hottentot fig (Carpobrotus edulis)
Over half of Britain's plant species are now non-native. Many of these were introduced deliberately for horticulture or agriculture, while others arrived accidentally, often as contaminants in trade goods. Not all non-native plants are invasive, but a small percentage have a significant negative impact on native biodiversity and ecosystems.
There are more than
1,700 non-native plant species established in the wild in Great Britain. While these species originate from every major continent, they are often documented by broader geographic regions rather than by every individual country of the world.
Below are examples of plants introduced to the UK, categorized by their country or region of origin:
Asia
China: Butterfly bush (Buddleja davidii), widely naturalized and often found on railway embankments.
Japan: Japanese knotweed (Fallopia japonica), introduced in the 19th century as an ornamental plant.
India / Himalayas: Himalayan balsam (Impatiens glandulifera), a tall annual with explosive seed pods commonly found along riverbanks.
Iran (Persia): Persian hogweed (Heracleum persicum), a large, invasive relative of the native hogweed.
Caucasus Region (Georgia/Russia): Giant hogweed (Heracleum mantegazzianum), notable for its massive size and skin-irritating sap.
The Americas
USA: American skunk cabbage (Lysichiton americanus), a swamp plant with large yellow flowers and a strong odor.
Canada: Canadian pondweed (Elodea canadensis), an aquatic plant that spreads rapidly in slow-moving water.
Chile: Chilean rhubarb (Gunnera tinctoria), a giant-leaved perennial often found in wet, coastal areas.
Argentina: Purple top (Verbena bonariensis), a popular garden perennial that has begun to naturalize in southern regions.
Brazil: Parrot’s feather (Myriophyllum aquaticum), an invasive aquatic plant often sold for garden ponds.
Europe
Spain: Spanish bluebell (Hyacinthoides hispanica), which often hybridizes with the native British bluebell.
Norway / Northern Europe: Sycamore (Acer pseudoplatanus), a well-established tree that has been naturalized since at least the 16th century.
Southeastern Europe / Turkey: Horse chestnut (Aesculus hippocastanum), the "conker" tree, introduced for its ornamental value.
Australasia & Africa
New Zealand: New Zealand pygmyweed (Crassula helmsii), an aggressive oxygenating plant that can dominate ponds.
Australia: Golden wreath wattle (Acacia saligna), one of several Australian species occasionally found in the wild or cultivated.
South Africa: Hottentot fig (Carpobrotus edulis), a succulent that forms dense mats on coastal cliffs.