Five invasive non-native aquatic plants banned from sale: our response.

Posted by Nicola Hutchinson, our Head of Conservation Programmes, England and Wales.

The problem of invasive non-native species (sometimes called alien species) is one of the best known environmental issues. Whether in towns or countryside many of us will have dealt with garden ponds or rivers choked with water weeds, watched Japanese knotweed grow and spread wherever it has taken root, and perhaps even admired the pink flowers of Himalayan balsam along a riverbank before thinking how much it has taken over.  Internationally, invasive species have long been recognised as one of the top threats to wildlife and the environment.  Ten years ago our own government set out a series of recommendations to deal with the problem and currently the European Union is considering a Directive as a way to better coordinate a response.  It's important stuff.

This is why it's great to hear the Government announce today that five of the most destructive invasive water plants will no longer be legally traded in England and Wales.  At last, some decisive and essential action.

Australian stonecrop, Crassula helmsii
one of the banned plants © GBNNSS

A range of specific measures are needed to really crack the problem,  with the most important of these being to curb the number of new incidences.  The primary mechanism for which is to simply ban the most troublesome from sale.  No matter how conscientious we as gardeners or landscapers may be, once invasive species are established in our gardens and parks they find their way over the fence into our streets and countryside.  Don't put them there in the first place and we've instantly removed a key pathway for invasion.

However, herein lies the twist with today's news.  The industry which trades in these problem species in England and Wales has been given a further 14 months to "adjust" to the new regulation.  This means that trading can continue until April 2014 - a move to allow existing stock and pre-orders of these invasive water weeds to be sold off.  Really, it beggars belief.  It's been agreed that these species are so damaging to our environment that it must become illegal for them to be sold, yet here we are inviting the biggest of all 'every last item must go' sale.  Are we really saying we want one last final push to get as many of these water weeds out of the shops and into the wild?

This sort of compromise agreement is one of the most frustrating aspects of environmental politics.  We are falling over evidence on the impacts of invasives; ten years ago the government recommended a ban on sale of the worst offenders, and 7 years ago the actual legislation was put in place to enable this to happen.  Yet, at the last minute, we've lost our nerve, ending up with a really smart move turning into a ridiculous one.

Government moved to halt the trade in ash trees, harbouring a non-native fungal invader, in response to the ash dieback crisis.  Questions were asked at the time whether this action was taken quick enough.  It seems we aren't learning our lessons well.

A sheep struggles through a channel choked with
Floating Pennywort © Trevor Renals

In these economic times, one appreciates the difficulties businesses may face when new regulations mean changes to the way they operate. However, in the case of invasive non-native plants, representatives of the horticultural and aquatic trades have been involved in discussions for well over a decade. Couple that with the legislation being put in place in 2006, the list of proposed species to ban consulted on in 2010, and this stacks up to ample time for traders and retailers to adjust already.  No-one in the industry can say they didn't know this was coming.


It makes me mad.  So I have to remind myself at these times that amidst the ditherings of others, here at Plantlife we've just been getting on with doing our best to implement solutions. Often that has meant direct action on the ground to clear established invaders from some of our most important places for wildflowers such as the Isle of Portland and the limestone cliffs of Torbay. And, with the principle of prevention being better than cure at the forefront of our efforts, we have researched which of the thousands of water and land plants available for sale pose the greatest threat to our native wildlife- this helps to hone our collective response, and gives the green light to the overwhelming majority of garden and pond plants available.   Indeed, to make it even easier for retailers and consumers we've worked with partners to publish reports and advice on which plants to choose as alternatives to those which cause problems (see our guides to landscaping and keeping ponds and aquaria without harmful invasive plants).

We've invested our time and resources into working out solutions to the invasive species problem because it really matters when it comes to conserving wild plants, incredible landscapes and other wildlife. Now we need everyone's help - do the right thing, it's easy, stop selling and stop buying these plants:

• New Zealand pigmyweed/Australian swamp-stonecrop Crassula helmsii
• Floating pennywort Hydrocotyle ranunculoides
• Parrot's-feather Myriophyllum aquaticum
• Water fern Azolla filiculoides
• Water primrose Ludwigia grandiflora, Ludwigia peploides, Ludwigia uruguayensis

And whilst you're at it, avoid these other ones too because they're equally as bad…

In the meantime, Plantlife applauds those retailers who've already made the shift to stop selling invasive plants, or who at least avoid the temptation to offer a 'buy one get one free' on curly waterweed!

For everything else you need to know about avoiding invasive plants and suggestions for fabulously non-invasive plants to grow have a look here.