Our Conservation Work
Fashion, World Wars, economic ups and downs, disease and simple old age have all been contributors to the decline of some of these collections and as a result historic varieties have already disappeared or are at risk now.
The Rhododendron, Camellia and Magnolia Group is a charity with conservation at the heart of its objectives and our work is dedicated to preserving our heritage of these three genera.
- gathering data into a meaningful list which identifies threatened varieties
- organising propagation of those threatened varieties
- collections in the wild are no longer possible so it is our duty to ensure what we have is preserved
- the hybrids our forebears raised over nearly two centuries represent an historic record which should be as complete as possible
Database of Extant Rhododendrons, Camellias and Magnolias
The first step towards realising our ambitions is to learn what is still in cultivation; only then can we know what we have lost. Luckily, we have excellent historic records to help us better understand the situation.
For the last eight years we have been assembling a list of extant plants of our three genera. Data is drawn from botanic and other major publicly accessible gardens, from the collections of our members as well as those from other societies, and from the general public who volunteer the information when they hear of our work. Checked carefully for naming against the international registers, we can determine rarity and assess the need for propagation to ensure a robust population is in existence.
This is a work in progress but the database currently records:
- 11,050 rhododendron hybrids, 6,845 camellias and 3,792 magnolias*
- 3,975 varieties of rhododendrons, 1,760 camellias and 770 magnolias
- 2,090 rhododendrons, 693 camellias and 299 magnolias are ‘one offs’ and require assessment**
*The rhododendron and camellia species lists are still being created and will appear in due course
** As more data enters the list, these statistics will be updated.
As well as identifying rarity, rhododendrons, camellias and magnolias ‘lost’ from the gardens where they were raised are being identified, propagated and returned.
Help us to expand this database by sending a list of the rhododendrons, camellias and magnolias you grow to conservation@rhodogroup-rhs.org
Conservation through micropropagation
History
The most recent threat to our three genera in the UK was the arrival of a rapidly spreading disease – Phytophthora ramorum – which can particularly affect ornamental rhododendrons and eventually kill them.
The South West of England was seriously impacted and this is where some of our most important collections of rhododendrons are to be found. This called for quick action both to eradicate the disease and to save the collections.
Luckily, the research facility at the Duchy College at Rosewarne is also in the South West, and thanks to external funding a rescue programme was set up there utilising a procedure known as micropropagation.
Licences were granted to use diseased plant material and a major conservation effort was launched. The speed of this initiative, together with the innovative work of Ros Smith, ensured that over 300 unique rhododendrons were saved.
Technique
The basic process involves stimulating plant cells (taken from fully developed floral buds) to develop into tiny growing shoots which can be grown on and eventually weaned towards independence, ready to be planted out.
Today
With Phytophthora ramorum mostly under control, external funding ceased but the conservation work of the laboratory goes on, now focussed on conservation of varieties threatened by other risks or made vulnerable through their rarity, often uniqueness. This is where the Rhododendron, Camellia and Magnolia Group has stepped in to help.
Thanks to the vision and commitment of John Harsant, in 2008 the Group embarked on a project to help preserve the ageing collection of Aberconway hybrids at Bodnant Gardens. With our financial support, twelve of its threatened rhododendrons were selected and micropropagated, and the famous ‘Penjerrick Walk’ re-established using the same technique.
Since that time, we have continued to support the Duchy College Laboratory in its efforts, through regular donations. We have developed an excellent working relationship with the team there, now led by Dr Naomi Beddoe with Ros Smith semi-retired but almost always in the lab!
Through supporting micropropagation we:
- are enabling gardens to conserve their threatened rhododendrons and reinstate their collections
- are establishing new collections in other gardens
- have safeguarded rare species such as Rhododendron vesiculiferum KW9485
- are facilitating the reintroduction into the wild of threatened species – a nearly extinct Rhododendron species from Portugal, for example
- have ensured threatened rhododendron hybrids are successfully propagated, returned to their place of origin and duplicate plants distributed to other gardens through our ‘safety in numbers’ policy
- are restoring ‘lost’ rhododendrons to the UK through the import of plant material from overseas collections
are funding further research into micropropagation techniques – successfully micropropagating camellias, for example, has so far eluded the scientists and our support might make the difference
 RUSSELL BEESON (Large).jpg)
 RUSSELL BEESON (Large).jpg)
Conservation through conventional propagation
Where it is possible, threatened rhododendrons are propagated from cuttings. This is a much quicker process but not suitable for diseased material or where vigorous shoots are not available. Very often, micropropagated plants are raised from the last surviving flower buds on a dying plant.
At the moment, rare camellias can only be propagated from cuttings or grafts. Luckily we have an excellent propagator working with us who is accustomed to working with less than perfect material.
With magnolias we are similarly fortunate to have an exceptional propagator who has managed to graft rarities for us so that we can distribute them to other gardens and raise the chances of their survival.
Conservation through identification
Maybe you have rhododendrons, camellias or magnolias in your garden you don’t know the name of and would like to. Maybe your garden contains plants of great age and there could be something rare or important growing there?
How can we help you?
Sadly, we aren’t able to come to your garden to identify what you are growing but if you send us high resolution photographs of flowers, leaves, bark and the whole plant, and tell us what size these features we will do our best to identify them for you and give you an idea of their importance. Please send to conservation@rhodogroup-rhs.org
How can you help us?
If you have been inspired by what we do, you can:
- support our conservation work through a donation to our ring-fenced Centenary fund
- send a list of the rhododendrons, camellias and magnolias in your garden to conservation@rhodogroup-rhs.org
- get involved and join us!
