Trees like the Leyland cypress and climbers such as Russian vine can grow so quickly that they are soon much too big for the garden.
Trees such as poplar and sumach have a tendency to sucker, sending up shoots all over the garden and even in neighbours’ properties.
Many ground cover shrubs like the snowberry or Hypericum calycinum spread via underground stems (rhizomes), sending up new plants and gradually taking over the border. Some bamboos also behave in this way, becoming a constant source of regret for the gardener.
Potentially invasive herbaceous plants and grasses, such as Japanese anemones and Phalaris arundinacea, form ever-enlarging clumps that require frequent division. Others, such as golden rod or weeping sedge also spread by seed, with seedlings popping-up in unexpected places where they are not wanted.
Bulbous plants such as Oxalis can produce tiny new bulbs, or offsets, which are scattered every time a clump is dug up, spreading the problem rather than controlling it.