Plant Alert; Find out how you can help stop Non-Native Invasives in their tracks!

Plant Alert; Find out how you can help stop Non-Native Invasives in their tracks!

Himalayan balsam (c) Amy Lewis

This week is Invasive Non-Native Species week! The fight against some of these species in the UK has been raging for decades, threatening our native flora and fauna.

Here, Kirsty Brown, Shropshire Wildlife Trust's Senior River Projects Officer, explains more about non-native invasive plants, what to look out for, and what you can do to help stop the spread at home.

Are you a gardener, allotmenteer or horticulturalist? You can help stop new invasive non-native species in their tracks!

The fight against invasive non-native plant species in the UK has been raging for decades. In the past, plant-collectors brought over beautiful species such as Himalayan balsam and Rhododendron ponticum.

These plants found the UK climate to their liking and soon became established in their new surroundings. Little did people realise back then that these plants would escape the boundaries of the manicured new homes of botanical gardens dotted around the country, and would creep out to establish themselves firmly in the wider countryside. You may have seen the Rhododendron coating wild hillsides in Snowdonia or Himalayan balsam turning your local riverbanks pink through the summer.

Many plant species found in the UK do not originate here, and, in this day and age, we have the delight of visiting garden centres and even supermarkets filled with a spectacular array of plant varieties and seeds from around the globe that we can choose to take home and plant in our gardens, which enrich our lives. So, what makes some of these plants a problem, but not others?

A non-native species of plant is one introduced to an area outside of its usual range, usually moved by humans, accidentally or purposefully. However, a non-native invasive species of plant is not only found outside of its normal range, but also has the ability to spread causing damage to the environment, the economy, our health and/or the way we live.

They are often so expensive to control and eradicate that in the UK we have a dedicated secretariat, the GBNNSS, to help co-ordinate efforts.

Giant hogweed

Giant hogweed

Some of these invasive non-native plant species are so heavily ingrained in the countryside that eradication is now impossible, and they out-compete native plant species.

Others cause health issues, for example the sap from Giant Hogweed causes horrible burns when affected skin is exposed to sunlight. Floating pennywort affects tourism, clogging slow-moving waters like canals, blocking boat access and preventing fishing.

As a gardener, allotmenteer or horticulturalist, you should ensure that any ornamental plants on your/your customers’ land stay within their boundaries, and to dispose of unwanted plants carefully and legally.

This applies to aquatic/pond plants, too. Information on the laws for England & Wales around what you need to do if you keep, grow, find or sell certain invasive non-native plant species and your responsibilities to prevent their spread can be found here.

If you are a retailer selling plants, including aquatics, top tips can be found via the BePlantWise pages here.

Thankfully, out of those introduced, only small percentage of plants cause a problem, and we can all play our part in preventing future issues.

Plant Alert Logo

If you notice an ornamental plant getting out of hand in a garden or pond, for example by becoming vigorous, hard to control, spreading rapidly by seed or from fragments etc., the best thing to do is report it via PlantAlert.

Don’t worry if you’re not sure if it is non-native or not – the team behind this system are experts and will review all records received. You can send in reports from your phone or your tablet/PC/laptop via the website.

PlantAlert is a collaboration between and the Centre for Agroecology, Water and Resilience at Coventry University and the Botanical Society of Britain and Ireland. Want to know more? Check out this YouTube video and follow on Twitter.

In addition, keep an eye on the GB Non-Native Species Secretariat species alert page. This is where upcoming invasive non-native species are added that appear likely to be costly to control in the UK, and how to report them.

Check out our Shropshire Invasive Non-Native Species Initiative project to find out what’s happening locally.

By taking action together, we can help protect our native wildlife and habitats for us and future generations to enjoy.


White-clawed crayfish: Austropotamobius pallipes

White-clawed crayfish (shed carapaces): Austropotamobius pallipes with Kirsty Brown - credit John Hughes

Kirsty Brown, Senior River Projects Officer.