Invasive Plant Risk

A number of well known and loved plants are among the 92 plants ranked as ‘critical’ in having the potential to cause significant problems and is classed as an invasive plant. This number includes widely grown garden pond plants along with 33 other aquatic species.

It is a worry for many that these plants could become notorious weeds just as precious garden introductions have. Some include; Fallopia Japonica (Japanese Knotweed) and Impatiens glandulifera (Himalayan balsam) these species are shifting the usual appearance of habitats and are overpowering the usual species.

Although the majority of non-native plants aren’t harmful, a small amount of these cause some considerable damage to the UK’s natural environment and with the government estimating these non-native plants are costing the UK more than £2 billion a year, they are defiantly hitting the economy hard.

Deterrent Principle

Almost 600 non-native garden plants were screened to measure each plant on factors including growth habit, ability to disperse and acceptance to herbicides, this study is known as ‘horizon scanning’. Those plants listed as ‘critical’ will now be fully risk assessed.

The table below lists a number of plants that may become insidious:

Garden Plants that may become Invasive:
~ Acaena novae-zelandiae (pirri-pirri bur)~ Cotoneaster horizontalis (wall cotoneaster)~ Ailanthus altissima (tree of heaven)~ Euphorbia amygdaloides var. robbiae

~ Pinus nigra (Corsican pine)

~ Typha minima (dwarf bulrush)

~ Quercus ilex (holm oak)

~ Quercus cerris (Turkey oak)

~ Ribes oderatum (buffalo currant)

~ Robinia pseudoacacia (false acacia)



We all like to have a variety of plants in our gardens to make it interesting and attractive to the eye. Having such a variety in our gardens then means that it is important for us to know whether they are going to take over the garden and affect the growth of our other plants. Blue iris Landscapes hope that you have found this article helpful in knowing which plants could become invasive, so beware!! If you would like more information on anything discussed in this article or any other gardening issue then please don’t hesitate to contact us.