An invasive plant can be defined as any plant that grows where you don’t want to and does it in a way that makes it hard to control. It doesn’t have to be a weed, and invasive plants are by no means always ugly specimens. They are able to spread so successfully through a number of traits: they grow fast, reproduce quickly, adapt to a wide range of environmental conditions, and can even alter their growth habits to better suit the new location. To help identify a few invasive garden plants, Express.co.uk spoke to Viktor Holas, creator of simplyswider.com, with six years of experience in gardening.
While many garden centres and nurseries continue to sell some selected invasive plants, the expert warned that invasive plants can cause “serious damage” and should be “avoided”.
Japanese knotweed
The first plant Viktor listed was Japanese knotweed as it is commonly known for the intensive damage it can create if lurking in a garden.
Probably one of the worst invasive plants in Britain, Japanese knotweed forms dense colonies along roadsides and railways, river banks, waste ground, building sites and around new developments – almost anywhere.
The expert said: “This plant is considered invasive because it can grow rapidly and outcompete native plants, forming dense thickets that can crowd out other vegetation.
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There are two features that make a plant invasive. First, invasive plants spread quickly and easily from one place to another. Sometimes seeds are carried on the wind or in running water, birds may eat them and distribute them in their droppings, seeds may cling to the fur of animals.
Parts of the plants themselves, often the roots, may be spread during road and bridge construction, plants may be dug up from gardens and dumped in the countryside, they can be carried stuck to boats, or planted to brighten up roadsides and developments after construction.
One way or another, invasive plants are often spread as a result of the actions, usually unintentional, of people.
Second, invasive plants damage native plants in their natural habitats by smothering them, taking over their habitats, stealing nutrients, drying out the soil, blocking waterways and replacing wild plants in their wild habitats. There is also often a secondary effect, when native plants are smothered insects that feed on them lose their food supplies.