Spotlight on… Rhododendron!

Rhodondendron (Rhododendron ponticum)

What is Rhododendron?

Rhododendron ponticum is one of the worst invasive species in the U.K. (as well as throughout Europe and in New Zealand). Rhododendron is a dense shrub that grows up to 8m tall. It has waxy, elliptical/oblong, dark green leaves that grow up to 22cm in length and bright purple-pink flowers. It is evergreen, so it is visible all year round.

It is important to keep track of Rhododendron because once it invades an area, few native plant species will survive, due to Rhododendron outcompeting them for resources (primarily light).

Rhododendron is covered by the Wildlife and Countryside Act 1981.  It is listed under Schedule 9 of the Act and Section 14 of the Act states that it is an offence to plant or otherwise cause the species to grow in the wild.

Where is Rhododendron?

According to our database, Rhododendron is found throughout Oxfordshire and Berkshire (see map below), but particularly in South East Berkshire. However, our database only includes information which people have provided to us (and we have collected), so a lack of records doesn’t mean that Rhododendron aren’t present in the area. All it means is that no-one has told TVERC they’ve spotted them… yet!


Have you seen any Rhododendron?

If you spot any wildlife when you’re out and about, share your records and photos with TVERC via our website. By letting TVERC know what you have seen you will help protect and improve your local environment by increasing the quality and quantity of data we hold.

Absence records are also very useful, so also let us know if you’ve been out and haven’t seen anything!

Your records can inform a variety of exciting biodiversity projects and help people make informed decisions about how to develop and manage land sustainably. We are a ‘not for profit’ organisation so rely on valuable help from skilled volunteers to improve our database.

Identification help

Rhododendron is pretty easy to spot, and the excellent guide by the GB Non Native Species Secretariat should allow for easy identification!

There is a useful app that is free to download called “PlantNet”. PlantNet allows you to take a picture of the plant and it will attempt to identify it for you. This is not 100% accurate, so you should always double check with other ID guides, but it’s often a good place to start in the identification of a difficult plant, and compare other app users’ images of that species with your own specimen.

Tips for recording

  • Always make sure you have permission to be on the land, we’d love records from every spot, but please don’t trespass!
  • Rhododendron flowers between May-June, so don’t just look for the flowers, the leaves are also quite distinctive!
  • Make sure you wrap up warm, let someone know where you’re going, and keep an eye on your surroundings – stay safe!
  • Rhododendron is easy to spot from a distance, so a pair of binoculars and a high vantage point would be a great start.
  • Common on acid, peaty or sandy soils in woodland, heathland, rocky hillsides, river banks, gardens and parks.

Find out more 

Check out the links below for more information on Rhododendron and how to identify it!

GB Non-native species secretariat

Online Atlas of the British and Irish Flora

NBN Atlas 

Spotlight on... Rhododendron leaflet PDF

Where should we direct our spotlight next?

If you are a recorder, a local recording group or just have an interest in a species, send us your suggestion for a species, along with some facts and a photo (if possible) to