Nature Notes
by Bob Thomas

Among the most beautiful flowers in the world are the passionflowers which bloom on a lattice-work of vines. The flowers range from pale non-descript tones to bright reds and the gorgeous regal coloration of our largest native species, the Purple Passionflower, Passiflora incarnata.

Passionflower vines are very aggressive, and once established, they may cover bushes and are very difficult to eradicate. That is their downside.
Their upside includes the flower's beauty, and serving as the place where beautiful orange, black and silver Gulf Fritillary butterflies lay their eggs and their caterpillars feed. Once you have this plant established in your yard, you are guaranteed to have fritillaries constantly flitting about.

The purple flowers are three inches in diameter, showing a lovely, yet complex, architecture. In Christian lore, they have long been associated with the last days of Jesus Christ, thus the name passionflower. There are five blue sepals and five similarly colored petals, together representing 10 of the 12 apostles, excepting Peter and Judas who distanced themselves from Jesus just before the crucifixion. Two rings of thin filaments, representing the thorns on the crown, encircle the reproductive organs. The wounds on Christ's body are depicted by the five pollen-bearing stamens, and the three stigmas (the part of the pistil, or female anatomy of a flower, that receives the pollen) represent the nails in the cross. The tri-lobed leaves symbolize the spear that entered his flesh, and the tendrils that help the vines climb by growing rapidly and wrapping around branches portray the leather strips that cut his flesh.

The fruit of passionflowers are locally called maypops, thus the colloquial name for the flowers and plants, too. They may be eaten fresh, or used to flavor ice cream due to their sweet aroma.

Passionflowers have a symbiotic relationship with ants. They provide ants a nutritious nectar via structures called extrafloral nectaries (nectar sources outside the flower), located at the base of each leaf. In return, the ants protect the leaves from predators, including the fritillary caterpillars. Such activities are much more common in the tropics than locally.
Some passionflower species actually have tiny structures that resemble butterfly eggs; they make gravid butterflies think that eggs are present, so they seek laying sites elsewhere.

Oh, yes. There is another local species that is not as showy as the purple passionflower. The Yellow Passionflower, Passiflora lutea, has yellowish-green parts of the flower and only slightly lobed leaves. It is quite common north of Lake Pontchartrain, but does not grab the attention that is common of its more elegant cousin. Close examination reveals, however, a stunningly beautiful cryptic twin that is easily overlooked by those who are less observant.

Also published in Delta Journal, The Times Picayune, August 12, 2007, and June 28, 2008.

Purple Passionflower (maypop), Passiflora                              An ant visiting an extrafloral nectary on
incarnata, flower and bud.                                                    a passionflower leaf stem.
Photo by Bob Thomas.                                                        Photo by Bob Thomas.

Yellow Passionflower, Passiflora lutea.
Photo by Bob Thomas.