Today I am giving a seminar on Passiflora. You can see the slide show here: Passiflora as a Multipurpose Fruit Crop for Temperate Climates
There are two species of Passiflora native to North America (and Mississippi). The smaller, non-showy species is Passiflora lutea. This has small flowers and small, purple fruit. It is a perennial, but with very limited ornamental potential. The second species is Passiflora incarnata, often referred to commonly as ‘maypops’. This species has large, showy flowers and large fruit.
Passiflora incarnata has been important in historical and religious contexts. It has been called the “Flower of the Five Wounds” to symbolize the crucifixion of Christ. Archaeological evidence in the southeastern U.S. identifies it as an important food crop for Native Americans since the Late Archaic period. The Algonkian and Creek tribes may have been the first to domesticate the plant and Europeans may have also consumed it after coming to North America. An early description of the fruit described it as growing with fields of corn and being a good summer cooling fruit.
Most Passiflora species originated in South America, especially Brazil. Some of the South American species are similar to P. incarnata, with P. edulis bearing a close resemblance. P. edulis is an edible passionfruit and is grown in many tropical areas. P. incarnata is also edible, but seedy and not as sweet as P. edulis. However, there is great potential for P. incarnata in North America as a ornamental and fruit crop.
Researchers in Florida and Georgia tried crossing P. edulis and P. incarnata. They were trying to make an edible fruit that could be grown in temperate climates. Of course, an added bonus is the extremely showy flowers that would be prized for ornamental value as well as an insect and bird attractant. This research culminated in the release of an ornamental cultivar, ‘Byron Beauty’. However, even though P. edulis and P. incarnata look similar, they are different species and crosses mainly resulted in sterile offspring. This is not of consequence for ornamentals, but is a problem in breeding for fruit-bearing vines. Hence, no fruit producing vines were released from the research program and no further work is being done.
P. incarnata is also known for its pharmacological properties. It is used as a sedative and antispasmodic in Europe and is an over-the-counter herbal supplement for headache sufferers in the U.S. Other potential uses could be uncovered with more research.
There is one major obstacle for P. incarnata to become a valuable ornamental vine. It is weedy and difficult to control. The root system can run deep underground and produce sprouts 20 feet away from the mother plant. Mowing the sprouts only seems to enhance the number of sprouts. Selection for a less vigorous and invasive individual would aid in it becoming an ornamental for home beautification and enhancement.
The native passiflora of North America deserve more attention for both ornamental and fruit purposes. They attract staggering numbers of bees and hummingbirds and produce copious amounts of fruit. It is also native to Mississippi and grows well in all soils, but especially poor soils. Therefore, it is something that both homeowners and researchers could put more effort into discovering.