Well done everyone that got this one right – it was a passion flower. To be more precise, it is ‘Empress Eugenie’ although this plant has such a tangled history of naming that it is also known by other names. It has been in the greenhouse for at least 10 years, ever since it was put up and I used to struggle with deciding whether it is really ‘Empress Eugenie’ or P. x belotii. The two plants were supposed to be subtly different and I was never 100% sure I had plumped for the right name. But checking again, so I don’t mislead you, it looks as though I was wasting my time back then and the two are the same, or at least all the hybrids of the parents can be called P. x belotii. So, this is a hybrid of P. alata, which is certainly not hardy, and the more or less hardy, common, blue passion flower (P. caerulea). In the past (and presumably still now) it is called P. alato-caerulea. Whatever it is called, this is a lovely plant that will easily reach 5m high and has tri-lobed leaves in mid green and big buds, singly in every leaf axil that open to these colourful and slightly fragrant flowers throughout summer. In my cold greenhouse it flowers for more than six months. In a mild garden it may be worth trying outside and, of course, it could be grown in a pot and moved into a greenhouse for winter, but overall this is not a hardy plant for the UK. The ten petals alternate between white and lavender and the zoned corona is quite spectacular.
Passion flowers are, structurally, very interesting. There are three bracts around the bud when it is young but these sometimes drop off (or are coloured in some species). The five sepals that hold the flower together in bud can be identified when the flower opens because they have a small hook at the tip, and in this passion flower they are white. The true petals are lilac. But it is in the centre of the flowers that things get interesting!
The male and female parts of the flower are combined to form an androgynophore and below this are concentric rings of filaments that form the corona. The outer parts lay flat against the petals and, presumably, the zoned colouring tells pollinators where to get the nectar. This is produced right in the centre of the flower, at the base of the androgynophore and the innermost filaments form a ‘brush’ that prevents the nectar being robbed by anything other than the pollinators. Passion flowers can be pollinated by a range of creatures including bats, bees and birds but it strikes me that these are typical bird pollinated flowers. More of that in a second.
The androgynophore is a column that includes the ovary but below that are the five stamens, held very precisely so that the anthers, which are hinged, are held facing down towards the petals. Then there is the ovary and then the three stigma lobes above that. The receptive surfaces of these also face down. It seems perfectly sensible to me that a humming bird, feeding on the nectar of this upward-facing flower, would get pollen on the top of their heads and then transfer that to the stigmas as they flit from bloom to bloom.
And so on to the name. I am afraid that eating passion fruits does nothing for your libido. The name refers to the way that Christian missionaries in Central and South America (where the genus has its base) in the 15th and 16th centuries used the plant either as a teaching aid or as a sign that their suppression of the indigenous peoples was worthy.
The tendrils represented the whips used to whip Christ, the fingered leaves the hands of his assailants, the ten ‘petals’ the apostles (not including Peter and Judas), the corona is the crown of thorns, the ovary the Holy Grail, the three stigmas the three nails and the five stamens the five wounds (including the lance wound).
In other cultures (because there are more than 250 species and they are grown around the world) they are more soberly known as ‘clock flowers’.
The passion fruits you find in supermarkets are the fruits of P. edulis which is a lovely thing with huge flowers but it is not hardy at all. I have never seen fruits on ‘Empress Eugenie’ and the fruits of the common passion fruit, though edible are not that tasty. But, around the world there are lots of other edible passion fruits. Passiflora incarnata (maypops) an herbaceous North American species, has traditionally been used as a treatment for insomnia and is still used in some ‘off the shelf’ remedies.
7/10 (it is not hardy)