The French plant health authorities have recently announced new findings of Xylella fastidiosa on two ornamental olive trees which are from two areas that were demarcated in 2015, one area for Xylella fastidiosa subspecies multiplex and the other for Xylella fastidiosa subspecies pauca.

The findings of infected plants all relate to existing outbreaks in Provence-Alpes Côte d'Azur regions.

The HTA urges traders and growers to continue to make careful decisions on the sourcing of plants - particularly for imports of Polygala myrtifolia, Olive, Lavender, Rosemary, Almond and Nerium oleander which are at present considered the most significant threat to the UK. These are not the only hosts of Xylella but the host species currently associated with most outbreaks of Xylella in Europe.

All growers and traders should take the following actions:

  • Ensure imported plants both originate from and are sourced from disease-free areas.
  • Source from known suppliers or visit suppliers to view their processes, procedures, bio-security arrangements and the plants they grow.
  • Isolate or quarantine new batches of plants and monitor them during the growing season for signs of the disease.
  • Ensure that plant passports arriving with plants are correct and keep the plant passport to aid traceback if necessary.
  • Follow the full guidance on
  • Subscribe to the HTAs weekly e-news updates to receive updates and advice on this and other relevant issues.

For more information
Horticultural Trades Association
Horticulture House
19 High Street
West Berkshire
T: +44 (0)118 930 3132
Fax: +44 (0)118 932 3453
NGGV: +44 (0)118 930 2092