Plant 79

Passiflora alata Curtis (Passifloraceae)


Wing-stemmed passionflower

The name Passiflora comes from the Latin, passio (passion) and flos (flower). The early Spanish missionaries in the Americas thought the flowers resembled elements of Christ's Passion: the corona represents the Crown of Thorns; the styles the three nails; the anthers the five wounds; the petals and sepals the ten faithful apostles. Meanwhile, alata refers to the four-angled, winged stems.

Passiflora is a large genus with about 450 species, many of which have edible fruits and beautiful flowers. Passiflora alata is native scrambler of the forest areas of Amazonian Peru through Amazonia to eastern Brazil. Passiflora alata is very similar in appearance to Passiflora quadrangularis but has smaller leaves, flowers, corona filaments and fruits.

Passiflora alata is a vigorous species with stems that can reach 10 m, using tendrils to climb through the canopy or along wires or a framework in the garden or glasshouse. Consequently, in cultivation restrictive pruning is required; otherwise a woody mass of stems forms in the centre of the plant. At Oxford Botanic Garden, Passiflora alata can be found growing against the glass of Conservatory on wires, where it provides shading during the summer. Pruning takes place in early spring. Generally, passion flowers do not need rich soils, but they do need the soil to be well drained.

The exotic-looking, fragrant flowers have similar sepals and petals that are green on the outside and a deep crimson inside. The corona filaments are wavy and banded red, white and purple. For pollination and therefore fruit set, temperatures of 16 Celsius or more are needed. In glasshouses there may be insufficient pollinators, so a helping hand may be necessary. The fruits are 8-15cm in diameter and a yellow to rich orange colour. Passiflora alata is often grown commercially for its fruits, although it is not one of the main commercial species. It will tolerate temperatures below 2 Celsius for short periods, fairing better at 7 Celsius or more. Propagation is very easy by either cuttings or seed.

Passiflora alata is a popular parent for breeding passionflower hybrids. One such hybrid, Passiflora x belotii (Passiflora alata x Passiflora caerulea) is well known in North America. The hybrid was first raised by William Masters at a Kentish nursery and named by John Lindley, in 1824, as Passiflora alatocaerulea. However, under the rules of plant naming, Lindley's name cannot be used officially, making Passiflora x belotii the correct hybrid name.

Further reading

Huxley A 1999. The new Royal Horticultural Society dictionary of gardening. Groves Dictionaries Inc.

Ulmer T and MacDougal JM 2004. Passiflora. Passionflowers of the world. Timber Press.

Vanderplank J 1991. Passion flowers. Cassell Publishers Ltd.

Lucinda Lachelin