A member of the Passionflower family (Passifloraceae), the Passiflora genus has about 500 species, four of which are found growing wild in Arizona: Passiflora arizonica, P. mexicana, P. bryonioides, and P. arida, which can be mistaken for P. arizonica except that it blooms during the day and its bracts are not sticky. Arizona Passionflower is unusual because it is a night bloomer.

Form: A climbing vine.

Lifespan: A short-lived perennial lasting 5-7 years.

Leaf retention: Cold deciduous.

Growth rate: Rapid.

Mature Size: 10' (3m) long.

Flowers: An elaborate, fragrant structure up to 2" (5cm) in diameter. Ten white tepals (five sepals resembling petals alternating with five petals) underlay dozens of fleshy filaments showing three color bands (pale blue or purple, white, purple from outside in). The filaments are crowned by five yellow-green stamens (pollen-bearing male) underneath three white stigmatas (female).

Bloom: Late summer and fall. This fragrant flower opens late afternoon for the night and closes after pollination. It may remain open the next morning if not pollinated. The five sepals open first, followed by the petals (see picture).

Bracts: The flower buds and fruit are surrounded by thin, tendril-like, many-branched bracts coated with a sticky, smelly fluid, seemingly to attract tiny insects. Digestive enzymes in the fluid suggest that this plant is poised to become carnivorous like the Sundew, especially in poor soil conditions.

Fruit: Round to oval shaped, about 1" (2.5cm) in diameter, poisonous when green. The fruit turns yellowish and falls off the vine when ripe and edible. The ripe fruit contains a small amount of gelatinous pulp, with a delicate flavor that is mildly sweet to tart, mixed with many small black seeds.

Leaves: Deeply cut with three major lobes, the side lobes having secondary lobes, forming 3 to 7 lobes, covered in fine hairs. They are stinky if crushed.

Stems: Hairy, dry to the touch, green or red, no thorns, herbaceous, becoming woody with age, with hairy coiling tendrils that assist climbing.

Roots: Non-invasive. Possible suckers from roots.

Wildlife: The flowers attract night-flying moths. It is a possible larval host to the Gulf Fritillary butterfly. Bees are known to visit the flowers before they are fully open if a cloudy late afternoon induces the flowers to open early (see picture).

Toxic / Danger: All parts are poisonous, containing cyanide, except for ripe fruit.

Origin: Arizona and Mexico.

USDA hardiness zones: 8b-10. This plant dies to the ground in hard freezes and regrows from its roots.

Heat tolerant: Yes.

Drought tolerant: Somewhat, depending on summer rains.

Sun: Full sun.

Water after becoming established: Twice a week to every two weeks, depending on appearance. More water is needed when fruit are developing.

Soil: Well drained, pH 6.6-7.8 (neutral to slightly alkaline). This plant is tolerant of soil types but prefers soil with some organic matter.

Mulch: No.

Propagation: Cuttings or seed. The seed may take several years of freeze/heat and wet/dry cycles to germinate.

Uses: Native plant specimen.