“I consider every plant hardy until I have killed it myself.”-Sir Peter Smithers, Swiss
I was reminded of this quotation when I saw native passionflower, Passiflora incarnata, growing along a rocky outcropping. My mind began to run wild with the possibility that maybe, just maybe, red passionflower, Passiflora coccinea, would overwinter in my Kentucky garden.
While passionflowers are predominately tropical there are two native passionflower vines that grow in Kentucky: Passiflora incarnata-maypop or wild passionflower; and Passiflora lutea-yellow passionflower. Both wild and yellow passionflower are herbaceous vines (they die to the ground each year) and can grow over 20 feet in one season. These native vines are a little slow getting started each spring, barely noticeable until about mid-June when real summer weather kicks in.
Wild passionflower is an extremely vigorous vine and can be found growing in dry sunny areas along rocky country roads and dry slopes. It is also commonly called maypop because the sweet, edible, oval-shaped passionfruit will pop open loudly if you squeeze them. The flowers are very showy but vary widely in color from a light blue (almost white) to a light lavender blue. Each flower is large, almost 2 inches across, and is open for only one day.
Yellow passionflower is found less frequently throughout Kentucky and prefers to grow in moist, semi-shady areas at the edge of woods or creeks. Its flowers are smaller than those of wild passionflower, only about 1 inch across, and are a soft yellow.
The leaves of passionflower can be up to 6 inches long, are lobed in varying degrees, and often finely serrated. This vine is a good climber, clinging by tendrils that emerge from its leaf axils. It can also be very aggressive.
Hardy or tropical?
While Kentuckians can only choose from two hardy passionflowers, there are hundreds of tropical species hardy in south Florida, southern coastal California, and Hawaii in the United States (USDA Zone 10 and warmer). Hardy or tropical, the flowers all have similar shapes. The tropical types come in dozens of colors from white to blue and red and every color combination in between. The foliage of tropical passionflower is almost identical to our hardy wild passionflower but remains evergreen in its native tropical regions.
Named for Christ
The blooms of passionflowers are strikingly “passionate” in color and appearance but this isn’t why they are called passionflower. Early Christian missionaries found the passion of Christ symbolized in the complex and showy flowers. The five petals and five sepals were thought to represent the 10 apostles present at the Crucifixion of Christ, the corona a symbol of the crown of thorns, and the three-lobed leaves a representation of the Trinity.
As a gardener I have to be willing to take a chance every now and then and try a plant I have never grown before. I always try to research plants before I buy them, but I have to admit that sometimes I fall in love with a new plant at first sight. If I am rewarded with just one year’s worth of growth I feel I have succeeded. The success is in keeping my garden plantings diverse, my gardening passion fresh, and attacking each exciting season with a new perspective.
My plant of choice this year is of course a red passionflower; my eternal optimism keeps me believing that it will indeed survive to see a new year. And if by chance it doesn’t, well, I will just start searching for something new to add to my garden next summer.