The Genus Passiflora
Passionflowers
Family: Passifloraceae
There are 561 species of Passiflora. Passiflora has a largely neotropic distribution, unlike other genera in the family Passifloraceae, which includes more Old World species (such as the genus Adenia). The vast majority of Passiflora are found in Mexico, Central America, the United States and South America, although there are additional representatives in Southeast Asia and Oceania.
Passion flowers have floral structures adapted for biotic pollination. Pollinators of Passiflora include bumblebees, carpenter bees (e.g., Xylocopa spp), wasps, bats, and hummingbirds; some others are additionally capable of self-pollination. Passiflora often exhibit high levels of pollinator specificity, which has led to frequent coevolution across the genus. Passiflora all provide as larval host for the gulf fritillary.
When getting plants established, you might protect the young seedlings from the gulf fritillary until they are more significant in size to handle herbivory.
Photo of passiflora arizonica by Miguel Gastelum, iNaturalist
Arizona has three naturally native Passiflora species, and a few that have naturalized. There are several more nearby native species found in Sonora and Baja California.
The genus name Passiflora comes from the Latin words passio, which means "passion", and flos, which means "flower". The name refers to the flower's symbolism of Christ's crucifixion. In the 1600s, Spanish Christian missionaries would explain each part of the flower in relation to the Passion of Jesus Christ. For example, the five petals and five sepals represent the ten apostles who were with Jesus during his passion, excluding Peter and Judas. The three stigma represent the nails that held Jesus to the cross, and the five anthers represent his five wounds. The filaments are said to represent the crown of thorns, and the leaves with three points represent the Holy Trinity.
Passiflora arida
Sonoran Passionflower
Along with the Arizona passionflower (Passiflora arizonica) this species is part of the foetida complex of species that used to all be considered the same, and are somewhat similar. Covering the developing flowers and eventually the fruit of both these species are a series of feathery bracts, which are covered in glandular hairs. The hairs themselves are quite sticky thanks to the secretion of fluids. As insects crawl across the hairs, they become hopelessly entangled and eventually die. So, does this make P. foetida a carnivore? After getting stuck, the insect bodies quickly decay. Laboratory analyses revealed that indeed, the fluids secreted by the sticky hairs contained lots of digestive enzymes, mainly proteases and acid phosphatases. The digested remains are absorbed by the bracts and translocated to the calyx, corolla, anthers, and finally to the developing ovules.
Photo by Matthew Lachiusa, iNaturalist
Passiflora arida on SEINET
The Sonoran Passionflower grows about 15’ tall and usually goes dormant unless it is protected from cold weather. In warm weather intricate purple and white flowers appear. Flowers are followed by green fruits that are somewhat hollow sacs that ripen to a yellowish color. Not much for eating. Plants go dormant in cold weather but re-emerge from roots in spring.
The species name, arida, meaning dry, in reference to where this species grows in relation to other species.
Full to part sun, moderate water when established, hardy to around 20°F.
Passiflora arizonica
Arizona Passionflower
This species is very similar to the Sonoran Passionflower, and is from the same proto-carnivorous complex (see notes under Passiflora arida).
Plants grow about the same height as P. arida, but the stems and leaves are somewhat more hairy/fuzzy.
Full to part sun, moderate water when established, good drainage, hardy to the teens, though plants will go dormant. Plants re-emerge from the roots in spring.
The species name, arizonica, refers to the reigon in which this plant is commonly found.
Photo by Usvaldo GC, iNaturalist
Passiflora mexicana on SEINET
Passiflora bryonioides
Cupped Passionflower
Smaller deciduous vine climbing up to 6’ tall, rarely taller. Most often found in rock crevices in cliffs, draping downward. Lavender and white, intricately structured flowers followed by fruits that are relatively more substantial than our other native Passiflora species. Plants re-emerge in spring from roots.
This plant is perhaps better grown in a tall pot and allowed to drape over the sides, though plants can climb too.
This species is native to grassland and oak woodland, often in steep canyons in rocky soils and cliffs in northern Mexico (Sonora, Chihuahua, Sinaloa and Guanajuato) and Arizona..
The species name, bryonioides, means “like Bryonia” a plant in the Cucurbitaceae.
Photo by Jack Dash, SEINET
Passiflora bryonioides on iNaturalist
Passiflora caerulea
Bluecrown Passionflower
Large vine growing to 30+ feet tall, evergreen in frost-free locations, deciduous in colder areas. This species has larger flowers, more typical of the more tropical passionflowers, purple and white, and very intricate and fragrant. Fruits start green and ripen to orange.
In South America, the plant is known for its medicinal properties, and is used by both the Toba and the Maka peoples. The fruits are edible, if somewhat insipid.
This species is native to South America. It has naturalized in parts of Arizona, like Bisbee.
The specific epithet caerulea means "blue" and refers to the blue coronal filaments.
Photo by Norberto Muzzachiodi, iNaturalist
Passiflora caerulea on SEINET
Passiflora incarnata
Blue Passionflower
Larger-flowered deciduous vine that can reach 25+’ tall. Purple flowers appear in warm weather followed by green fruits with white flesh.
Full to part sun, regular to moderate water, root hardy to 10°F.
The fruit is edible fresh, juiced, or made into syrups or flavoring.
Native to the southern United States from Florida to Texas.
The species incarnata means 'to make flesh' or ‘flesh colored’, referring to the fleshy fruits.
Passiflora mexicana
Mexican Passionflower
Deciduous vine growing up to 25’ or more high. Bilobed leaves are less fuzzy than our other native passifloras. In summer flowers appear which can vary in color from purple, to pink, red, or even pale, almost white flowers. Flowers have a mothball-like scent. Fruits follow the flowers which are small, start off green and darken to purple, and are juicy.
Plant in part sun to even shady conditions. Plants are often found climbing mesquites and other trees.
Found in thickets near riparian zones and washes from 2,500-4,000 ft. in Arizona, and south along the western edge of Mexico.
The species, mexicana, refers to where the plant is most commonly found.
Photo by Liz Makings, SEINET
Passiflora mexicana on iNaturalist