Easter … a time for Christian celebration, for hares, for egg-rolling and for fancy bonnets … is also a time when the passion flower comes to mind, given its name for a variety of alleged reasons. The circle of petals is said to represent the crown of thorns placed on Jesus’ head during his crucifixion; the three stamens represent either the Holy Trinity or the three nails which secured Jesus to the cross; the ten petals are said to stand for the ten disciples who were no part of Jesus’ betrayal or denial; and the three-day life of the bloom of the passion flower is held to epitomise the three days Jesus’ body spent in the tomb. Whatever your personal view of these comparisons, gentle reader, it is an indisputable fact that one member of the family of plants called Passiflora … the passion flowers … has gained the Royal Horticultural Society’s (RHS) Award of Merit; and this honour was bestowed on Passiflora caerulea, the blue passionflower, otherwise known as the common passion flower … and the name can be written as one word or two.
Passiflora caerulea is a vine … a plant whose stem requires support and which climbs using twining tendrils or creeps along the ground … which came originally from Brazil and its immediate neighbours. It can, in the correct circumstances, grow to an impressive ten to fifteen metres in height, which is between 30 and 50 feet in old money, supporting itself by clinging to other trees. Passiflora caerulea is widely cultivated in mild, temperate countries as a wall-climber or as groundcover, and readily becomes an invasive alien, as has happened in Spain. The RHS website reports that, “Passiflora caerulea is a vigorous large deciduous or semi-evergreen climber with twining tendrils. Leaves are dark green, with 5-7 finger-like lobes. Flowers grow to 8cm in width, white, with blue and purple coronal filaments. Fruits are ovoid, 4cm, orange. It is a fast-growing climber for sun or partial shade, which thrives in moist but well-drained soil. In cold areas, grow in a container and overwinter indoors. Note that due to its vigorous nature in some gardens it has the potential to become a nuisance.” The RHS suggest that it is suitable for wall-side borders, city and courtyard gardens, patios and cottage and informal gardens, adding the caveat that it is sub-tropical, suggesting that it will struggle to thrive in central Scotland. However, Kenneth Cox and Raoul Curtis-Machen, in their exemplary book Garden Plants for Scotland first published by Frances Lincoln in 2008, write: “In milder gardens Passiflora caerulea may remain evergreen and can flower well into the autumn.” So, although one never knows, I would suggest that a large, heated conservatory would be a necessity in our climate.
During the Victorian era the flower was very popular, the slightly fragrant, showy blue, white and purple flowers with their prominent fringe of coronal filaments attracting many an admiring glance during each bloom’s few brief days of glory. These flowers are some ten centimetres in diameter … call it four inches … and are later succeeded by the fruit in the form of an oval orange-yellow berry typically six centimetres long and four centimetres in diameter containing numerous seeds. These berries are edible but are very bland to human taste buds. The plant’s purpose in producing the berries is not specifically to have them eaten by humans but to have them consumed by animals and birds, which then fulfil the plant’s purpose by distributing the seed in their droppings. But somehow I doubt if this last matter will be of much concern to a Scottish gardener!