Plant Categories

In recent years aquatic plants have become a major invader. The cost of removal and control runs into many millions of dollars. These invasive aquatic plants include Salvinia (Salvinia molesta), and Cabomba (Cabomba caroliniana), both of which are ‘Weeds of National Significance’ (WONS). Given the serious threat that invasive aquatic weeds present it is essential to seek sound advice before any purchase. There are many alternative plants which are more suitable for home aquariums and garden ponds.

Gardeners often choose trees and shrubs with showy persistent berries for winter colour in their gardens when flowers are scarce. Unfortunately these berries often attract birds and small mammals that unwittingly aid the spread of these unwanted plants into bushland and open spaces. Not all plants that bear berries are invasive, such as the majority of Australian native Lilly Pillies. Make sure you seek sound local advice regarding appropriate plant choice.

There are a number of bulbous plants that have become invasive, largely through the dumping of garden waste. Some of these plants are behaving aggressively whilst others are adventitiously taking advantage of the growing conditions to naturalise. Whilst not all bulbous plants are invasive some are becoming serious threats, with Kahili Ginger (Hedychium gardnerianum), Glory Lily (Gloriosa superba) and Taiwan Lily (Lilium formosanum) amongst the worst. Seek sound advice before planting bulbs and similar plants. Whilst most have spectacular flowers consideration must be given to assessing their invasive potential.

This very useful group of plants are often used to cover unsightly objects or provide green barriers and groundcover.  These attributes make most climbing and groundcover plants an effective plant choice. Unfortunately there are several species that are now recognised as invasive threats, currently invading bushland and smothering native vegetation. There are many alternative plants available that are non-invasive.

Mainly chosen because of their various architecturally interesting forms and drought hardiness, yet some are considered invasive. Mislabelling with incorrect species names has been an occasional problem. To reduce further spread of invasive grasses, seek professional advice at your local garden centre, read all labels carefully and avoid purchasing from any other source. There are many native grasses commercially available from your local garden centre that provide a safe alternative.

Succulent plants have become very popular due to their drought hardy status and architectural appeal.  Many succulent leaved plants are non-invasive, however there are a number that can rapidly spread from dislodged plant parts, leaves or by seed. In many cases a plant that is acceptable as a pot plant should not be planted in the garden or disposed of carelessly. Be sure to read the plant label carefully and ask for advice about the non-invasive succulents at your local garden centre.

Some people may only recognise invasive plants as being water weeds or rampant climbing plants. A significant amount of invasive plants in urban areas are simple trees and shrubs. The invasive trees and shrubs that cause destruction of habitat in natural systems usually produce prolific quantities of seed that germinate readily. Some plants in this category appear as invasive in more than one state, territory or region. They are becoming serious threats and it would be prudent to choose a non-invasive selection in adjacent states or territories. These threats include Yellow and Black Running Bamboo (Phyllostachys aurea and Phyllostachys nigra), shrubs like Pink Periwinkle (Catharanthus roseus) and our most invasive palm, Cocos Palm (Syagrus romanzoffiana).

Willows were introduced to Australia for stabilising watercourses and road fill and as garden ornamentals. Most willows are declared noxious weeds in Victoria and are Weeds of National Significance (WoNS) except Weeping willow Salix babylonica, Pussy willow Salix reichardii and Salix calodendron. Care should be exercised when planting any willow as it has the potential to become invasive.