The European Botanic Gardens Consortium

Home Page




European Initiatives



vert bar Home Page > Projects > Invasive Alien Plants

Sharing information, and policy, on potentially invasive alien plants in Botanic Gardens
Last updated: 25 October, 2018

Botanic Gardens hold large and diverse collections of plants, the majority of which are exotic, and many of which may be new to cultivation. Such plants may be given every encouragement to flower and adapt to their new home.
It is now recognised that there is often a lengthy lag phase between when a species becomes naturalised and represents no more than an innocuous introduction, to when it may become highly invasive. To date such transitions have usually proved to be unpredictable and unexpected.

An EU regulation on the prevention and management of the introduction and spread of invasive alien species (No. 1143/2014) came into force on the 1st January 2015. The new regulation aims to address the adverse impact alien invasive species have on biodiversity, ecosystem services, human health and the economy in the EU Member States.

The Regulation will restrict the use, trade and transport of invasive alien species, as well as management and control measures, underpinned by a list of invasive species of EU concern which will be compiled by Member States and regularly updated and reviewed every six years. The initial limit of 50 species has now been removed and this will enable Member States to take specific actions on invasive species of national concern.

It is vital that Botanic Gardens take steps to prevent future problem taxa from establishing through their collections

Initiatives such as DAISIE and North European and Baltic Network on Invasive Species (NOBANIS) as well as National Initiatives, such as Harmonia - Invasive species in Belgium provide detailed databases, but it can be difficult for Garden managers and curators to obtain summary lists that provide at a glance indications of problem taxa.
The European Plant Protection Organisation (EPPO) provides data sheets and Pest Risk Analyses to over 60 invasive alien plants.

The European Alien Species Information Network (EASIN), launched in 2012 by the European Commission, is an online platform facilitating the exploration of existing information on alien species from distributed sources, supporting scientific assessments and the implementation of European policies on alien species (e.g. EU Regulation 1143/2014).


The Scope of this European Consortium initiative therefore, is to :-

  • Compile lists of known invasive plants from acroos Europe, as well as those demonstrating 'weediness' at a Garden, Local or Regional level, in order to highlight cultivated taxa of concern, or potential concern across Europe.
  • Identify emerging problem taxa in the large, and diverse, botanic collections, especially in an era of Climatic Change, so as to alert collection holders to their potential risk in terms of invasiveness.
  • Foster vigilance through sharing early recognition of these newly problematic, or potentially problematic, taxa.
  • Ensure responsible, pro-active policies in Botanic Gardens and other plant collections, and apply these in a coherent manner across Europe.
  • Encourage gardens to engage with the public by informing them of the risks of introducing certain species into the wild, and how to recognise these species.


  • BELGIUM Harmonia, 25th Nov 2009. (16/08/2008)
  • CROATIA Boršić, I., Milović, M., Dujmović, I., Bogdanović, S., Cigić, P., Resetnik, I., Nikolić, T. & Mitić, B.: Preliminary check-list of invasive alien plant species (IAS) in Croatia. Nat. Croat., Vol. 17, No. 2., 55–71, June 30, 2008. Zagreb.
  • CYPRUS --
  • CZECH Pysek et al. (2002) Catalogue of Alien plants of the Czech Republic. Preslia 74: 97-186
  • ESTONIA Heiki Tamm (pers comm 30/05/2007)
  • FINLAND Leif Schulmann (pers comm 29/5/2007)
  • FRANCE Muller, S. (2004) Annex in Plantes invasives en France, Publications Scientifiques du Museum. CPN 62. Actes du colloque de Brest "Les plantes menacees de France, 15-17 October 1997.
  • HUNGARY Antal Radvánszky (pers comm 23/01/2007)
  • ICELAND --
  • IRELAND Reynolds, S. (2002) A catalogue of alien plants in Ireland. Occasional papers No. 14, National Botanic Gardens, Dublin.
  • IRELAND Invasive Species Ireland website
  • LATVIA Ludmila Vishnevska (pers comm 11/06/2008)
  • LITHUANIA Vida Motiekaityte (pers. comm.); NOBANIS (Nov 2009)
  • LUXEMBOURG Thierry Helminger (pers. comm 15/01/2007)
  • MALTA --
  • PORTUGAL Decreto-Lei nº 565/99 de 23 de Dezembro taxa marked (1) in the Appendix are considered invasive.
  • ROMANIA EPPO reporting service: 2006/216, Invasive alien plants in Romania
  • SWITZERLAND DAISIE; Anne-Sophie Dunand
  • UK BSBI Atlas 2000
  • UK GB Non-native Species Secretariat
  • UK PlantLife UK - Alien plants


    Spreadsheet of invasive alien plants across European countries - a tool for managers of collections throughout Europe

    1. Compile, and make freely available, a spreadsheet of taxa from European National lists (right) to show those known to be established, but not invasive (x), of known invasive tendency (xx) and proven to be invasive to highly invasive (xxx). In addition taxa that have demonstrated invasive or problematic behaviour within garden situations (gg), or are known problems (ggg).
      Legislation is now being enacted in several European countries (France, Portugal, Spain, Ireland), and plants banned for sale or movement are marked with a € symbol. note that a single € may not indicate the plant is yet found in the wild in that country, but where the plant is already a problem it is marked €€ or €€€ as above.
      Encourage Gardens, through their National Networks, to provide information in a timely and regular manner. The table has been colour coded, where data exists to show an approximate Atlanic/Continental/Mediterranean climate zones. This was on the basis of the data provided by France, which uses this breakdown. This should help to quickly identify invasive tendencies in countries with similar climatic conditions.
      6 July 2009: Where changes or updates have been made to the spreadsheet, the species name is highlighted in dark blue
      March 2012: Where bans for sale have been introduced, € symbols are used (see above).
    2. Compile and synthesise Policies, where these exist, to assist Gardens to share and develop best practice guidelines and policies.
      Sample Policy documents:-


    1. If the project is to attract interest and prove useful, the compiled lists need to be both as complete as possible, and be kept up to date.
    2. An early warning page and potential alert system needs to be developed (cf. EPPO Alert Lists)
      • I have added a column for EPPO Alerts to the spreadsheet (14th August 2008), even though some plants are still not recorded in the wild from our region.
      • I have adjusted the EPPO column to reflect the EPPO Lists of Invasive Alien Plants page (5th May 2013).

    For further information, please contact:
    Matthew.Jebb at
    Chairman, PlantNetwork
    : the Plant Collections Network of Britain and Ireland.
    Member of the European Botanic Gardens Consortium.


    Countries for which data has been compiled