The maypops are forming. Why are these round green balls hanging off vines growing along fences or outside trees at the edge of woods called maypops? Simple. They pop under foot when stepped on. This fruit of the passionflower vine (Passiflora incarnata) when fully mature begins to shrivel and the bright green color takes on a yellow tinge. Peel off rind, pull apart or slice the pop in half, scoop out the pulpy seeds. Suck off the pulp then eat the seeds. Similar to eating around a persimmon seed, but not the actual seed unless you are a deer or one of the other 28 wildlife species that love persimmons. Maypop connoisseurs say the green maypops are better cooked, but the ripe yellow ones are best eaten raw. The flavor is somewhere between an apricot and guava.

Most passion flower species are neotropical, but we do have two subtropical species that grow wild in Oklahoma. Our purple passionflower (Passiflora incarnata) is one of the toughest passionflowers in the 550 or so species in the Passifloraceae family. It grows throughout the eastern US and is the state wildflower of Tennessee. This hardy perennial bears complex flowers that begin blooming in July along woody vines that ramble 30 feet. The leaves are usually three lobed. The caterpillars of the Gulf Fritillary butterfly (dark orange with black spines) specifically eat only the leaves of both the purple and stinking passionflower. Zebra longwing larvae (white caterpillars with black dots and spines) feed mainly on passion vines. The Variegated Fritillary caterpillar (orange and white stripes with black spines) is not so picky and can also be found munching on purslane, moonseed and other plants.

Root systems run deep and sometimes as far as 20 feet away from the mother plant. The passionate plants grow in abandoned fields, along railroads, and in thickets, but not within forests or wet areas. They are considered grassland biome inhabitants (other major biomes are tundra, forest, aquatic and desert). A biome: Large natural population of plants and animals that occupy a habitat, like a grassland. Passionflowers can be propagated from seeds or cuttings. Expect 2-3 years before flowers and fruit.

Each 2” to 3” passionflower ‘flower’ has five green sepals that support the lavender, blue or white petals. Above the petals is a ring of colorful fringe called the corolla. The five male stamens rise above and fan out like spokes of a car wheel. The tallest structure in the middle is the all-important ovary with three styles, each with a sticky stigma to receive pollen. The purple passionflower can be self-fertile, but needs humid days and pollinators. The pollen is heavy and sticky. Carpenter bees are more efficient pollinators than honey bees, but bumblebees, hummingbirds, wasps and even bats participate.

The yellow passionflower (Passiflora lutea) is another species of passion flower that grows in Oklahoma. This is not self-fertile nor showy. It somewhat resembles the wild creeping cucumber vine Melothria pendula. Yellow passionflowers are small and, well, yellow-green to white in color. The creeping cucumber has small yellow flowers. Both plants produce black fruit. The passion flower fruit has been used to make ink, but the cucumber fruit is the mother of all laxatives. Use your nose to tell the difference because the cucumber vine smells like a cucumber.

Cool thing about the yellow passionflower is it has its own devoted small black bee, the passionflower bee, that only collects pollen from the yellow passionflower. That’s it. It’s a solitary bee. The tiny rare bee collects nectar and pollen to feed its larvae in the underground nest but seems not pollinate the yellow flowers! That task belongs to other pollinators.

Passiflora edulis is a light purple South American passionflower. The seed pods are the secret ingredient used to flavor Hawaiian Punch! The Columbian Passiflora parritae has brilliant red blooms but is facing extinction. Hummingbird pollinators are moving to higher altitudes as the climate changes. The night-blooming Passiflora mucronate (SE Brazil) produces 4” white flowers pollinated by bats. In the southwest US, leaves of Passiflora foetida truly stink if damaged, but are coated in a thick sticky layer with digestive enzymes that can trap and (use your imagination) insects and small animals (think Venus flytrap).

Passion flower was the name used by 17th century Catholic priests in Peru in an attempt to relate the familiar flower’s cross shape and crown of thorns to the religion. Maypop comes from Powhatan maracock. Powhatans were Algonquin people of Virginia and some of their words you may know: opossum, hickory, terrapin, tomahawk and raccoon.

Passionflower concoctions have medicinal properties as a diuretic, sedative, anti-inflammatory and treatment for insomnia. Purple passionflower contains crisin, a chemical that enhances testosterone level, so one could say it is a guy aphrodisiac.

Try your hand at growing a maypop. It’s worth the wait.