At last we meet! A picture of Dr Les King, the Passiflora Cultivar Registrar, coming face to face with hybrid KC13. He pronounced himself satified that P. kermesina x P. caerulea is indeed the P. 'Amethyst' cross. He has also done a great deal of research at Kew Gardens re the origins of P. 'Amethyst' and has published et al in Passiflorunde, 10(1), 2-13, 2002, Leslie A. King, Emil Kugler, Axel Frank and Christopher Davis.
There has been a great deal of interest in doing this cross as it was thought that P. kermesina and P. caerulea may be the parents of P. 'Amethyst', which is of unknown origin & may be over 100 years old. It is the best selling Passiflora hybrid in the UK. The original P. x kewensis is thought to be the same cross as this. A quite different hybrid with pink flowers & white filaments, thought to be P. racemosa x ?, is currently widely sold as P. x kewensis so I will wait until the naming experts sort it out before applying that name here.
P. kermesina was thought for many years to have been lost both in the wild & in cultivation. Thanks to work by Dr. Roland Fischer, Axel Frank, Dr. Reto Gamma & Mauro Peixoto, it has been rediscovered in the wild in Brazil. From his plant Roland kindly sent me a P. kermesina x P. caerulea fruit. Pictures of one of the best clones that I grew from it are linked to above. None of the plants shown here have been named as we are waiting to see the full range of flowers produced before selecting the best...which is Roland's tetraploid, Passiflora 'New Amethyst'. It is unlikey we will name any of the others.
Our conclusion that this is indeed the P. 'Amethyst' cross, although all our plants have predominantly 5 lobes. Note that Roland used a 9 lobed P. caerulea however so the lobe difference between his plants & P. 'Amethyst' is not significant. In any event P. 'Amethyst' does occasionally throw up 4-5 lobed leaves.
Finally, despite the excitement, I would comment that apart from Roland's tets
of this we have merely repeated a cross done many years ago. P. 'Amethyst' is a
great cross but a weakness is its tendency to lose colour especially at the
beginning & end of season. There are now approximately 500 known species of
Passiflora & there are a huge range of new hybrids coming online, including Dr.
Roland Fischer's other tetraploids. Mauro Peixoto states that the recently
rediscovered & shared P. loefgrenii (a stunning flower) is better than P.
kermesina colour wise, and P.miersii, different P. amethystina's & others are
proving very interesting & possibly hardy parents, so we have to move on and
produce even better hybrids.