Argyll and Bute has been invaded by several new species – of plants! Many of our gardens have been greatly enriched by the introduction of plants from abroad but a small number like rhododendron ponticum, Japanese knotweed, Skunk Cabbage, Gold Deadnettle, Himalayan or Indian balsam and Parrot feather are highly invasive.
They are a big problem in the wider environment threatening our habitats and native species and they can be an issue in the garden too. It’s difficult and expensive to control these species but many are widely available with little indication of the damage they can do if they are allowed to escape into the countryside or disposed of carelessly. The threat to our biodiversity, native species and habitats from these plants is very serious.
You should always be aware of what you are buying and growing and make sure you avoid using plants know to be invasive. There are always alternative plants better suited to gardens. If a plant is unfamiliar to you make sure you do some research. Be wary of any labels which use terms like ‘vigorous’, ‘spreading’, ‘fast-growing’, ‘self –seeds’ and ‘good ground cover.’
If you are exchanging plants with friends you should think about how what you are offering could spread. Much of the problem with Himalayan balsam is down to gardeners donating seeds. Watch out for introducing an alien species as a ‘hitch – hiker’ as many invasive pondweeds in particular as introduced to gardens this way. It’s a good idea to quarantine newly bought pond plants to see what else might come with it. Garden waste should be composted to provide organic matter to feed your plants and cut down on costs. If you’re buying topsoil it’s always a good idea to try and see it before you buy it as this is how many alien species make it into our gardens.
You can find some useful web addresses on the council’s website on our Invasive and Harmful Plants page.