Passiflora quadrangularis

The Passiflora quadrangularis, also known as the Winged Passionflower, gets its name from the characteristic appearance of its quadrangular stems with sharp and membranous angles. It is one of the most beautiful passionflowers and a tender tropical vine in its natural habitat. It will reach more modest but still impressive dimensions when grown in the shelter of our greenhouses and verandas. It produces large and beautiful, highly fragrant flowers with carmine red petals topped by a curly violet and white filaments crown. This botanical species produces edible fruits, which are green-yellow and are sometimes called grenadines. They are mainly consumed as fruit juice. Although susceptible to frost, this passionflower is not only sumptuous but also more resistant to most passionflower diseases.

Primarily native to tropical areas of South America, passionflowers belong to the large family of Passifloraceae, which includes 400 species and numerous spontaneous or horticultural hybrids. The Passiflora quadrangularis, sometimes called the Giant Granadilla, is native to the floodplains of hot and humid tropical forests in Central and South America. In its natural environment, it can reach heights of over 40m (131ft).

This climbing plant attaches itself to its support using tendrils, reaching heights of over 6m (20ft) when grown in a large pot. It stands out from other passionflower species with its quadrangular stems adorned with small wings. These stems are evergreen, climbing and tendril-bearing. They bear entire, heart-shaped leaves measuring 7 to 13cm (3 to 5in) in length and 5 to 15cm (2 to 6in) in width, which are perfectly smooth and light green with dark green veins. These leaves are carried by long petioles shaped like gutters and have six glands. Its flowering period extends from early summer to early autumn, with large solitary flowers measuring 10cm (4in) in diameter continuously appearing on the plant. These pleasantly fragrant flowers have five large rose-red petals, green wash on the inside, and greenish undersides. The central crown is striped with white, pale violet, and dark purple. These colours give this flower a unique beauty. The stamen cluster is cream-white. The unusual shape of the flower is relatively brief. The petals and sepals curl, while the filament crown folds and straightens to avoid self-pollination. Once pollinated, the flowers give way to beautiful, edible, tasty oval fruits that turn orange when ripe. They measure 20 to 25cm (8 to 10in) in length and are covered with thick, fleshy skin. The fruit contains numerous flat seeds.

This non-hardy passionflower will delight owners of large, warm greenhouses or beautiful verandas. It thrives in ordinary but rich, moist, well-drained soil in a sunny and sheltered location. Pruning at the end of flowering involves reducing the branches to maintain a beautiful habit.

Note: Root growth is inhibited in a small pot, encouraging flowering. Conversely, root growth is encouraged in a large pot to the detriment of flowering.