A bloom by any other name?
03.26.26
By Paul Hormick
Springtime brings the bright yellow of sunflowers and the scarlet and pink of peonies. As the days grow longer and temperatures warm, lilacs, marigolds, tulips, and daisies paint our gardens in lavender, indigo, and a rainbow of other colors. But of all the blooms of the world one stands alone. Because it is black. Yes, that’s right, black. The black bat flower (Tacca chantrieri) has blooms the color of pitch and coal. Roses may be red, and violets blue, but you have to admit a black bat flower is something pretty cool.
Why would a plant evolve to be black or nearly so? This is an evolutionary puzzle and a topic that prompts debate among biologists, gardeners, and horticulturists.
So named because the large blackish bracts that spread around this plant’s flowers resemble the wings of a bat, this evergreen perennial is also called tiger beard, cat’s whiskers, and devil flower. It’s easy to imagine the bat flower also earning the name of “old man” or “hippie” flower due to the white bracteoles, eight to ten inch long, which dangle from the flowers like an old man’s whiskers.
The bracts, which are specialized leaves, can be huge, up to 12 inches across and are often mistaken for the plant’s flower. The flowers themselves stand atop long stems and cluster within the embrace of the bracts. As buds, the flowers start out greenish, like the rest of the plant, but darken as they begin to bloom. The coloration is not truly black but more of a dark, brownish purple, with a tinge of green. Once the flowers bloom, the fruit is small and fleshy.
Described and classified by French horticulturist and landscape designer Edouard André, the black bat flower is a member of the yam family, yes like the yams you eat at Thanksgiving. It is endemic to the tropical and rain soaked evergreen broadleaf forests of southern China and southeast Asia, preferring to grow along streams and slopes. Its natural range extends as far east as Tibet.
Already quite scarce in the wild, the bat flower—much like many species of bats— is threatened by forest fragmentation, over exploitation, and habitat destruction. The flower has been accidentally released or purposely planted in the wild outside its natural range and has been found growing in other tropic environments, such as Ecuador, Costa Rica, Panama, the Hawaiian Islands, and the Republic of Congo. It is not known to be invasive in any of the environments to which it has been introduced.
Flowers are nature’s billboards. Plants’ blooms are saying to bees and butterflies, “Hey, I’m over here! Grab some free nectar and come pollinate me!” Flowers have thus evolved eye-catching petals of yellow, magenta, cyan, and other striking colors. Why would a plant evolve to be black or nearly so? This is an evolutionary puzzle and a topic that prompts debate among biologists, gardeners, and horticulturists. There also seems to be uncertainty over whether the black bat flower is mostly self-pollinating or if the plant is pollinated by flies and beetles that are attracted by the flower’s subtle scent of decaying flesh.
Gardeners prize the black bat flower for its unusual beauty, and it makes for an ideal houseplant. The flower lives in the shaded understory of forests, but professional gardeners advise that you should still ensure that the flower receives some natural sunlight for a portion of the day. You’ll also want to maintain a fairly generous watering schedule. The plant likes humidity, so it may not make for the ideal houseplant if you live in a more arid environment like Yuma or Tucson, Arizona. One reason for this plant’s popularity is that it can bloom up to eight times in a season. If kept indoors, the bat flower rarely produces seeds.
Pet owners may want to be careful when choosing the bat flower as a house plant, as it contains calcium oxalate crystals, which can sicken cats and dogs who munch on stems or leaves. While not considered toxic to humans, this plant may cause allergic reactions for some folks. Gardeners and others should thus be careful when handling it.
Closely related, in the same genus, is the white bat flower (Tacca integrifolia) It is native to the same parts of the world as the black bat flower and grows in similar habitats. It has the same black flowers but is distinguished from the black bat flower by the ghostly appearance of its large bracts. It is also grown in gardens and as a house plant, although it lacks the popularity of the black flower.
Research published this year confirms what traditional medical practitioners have known for hundreds, possibly thousands, of years: the black bat flower possesses curative powers. Besides containing compounds with anti-inflammatory properties, the flower also contains compounds called taccalonolides, which can suppress and kill cancer cells. And the bat flower compounds may be more effective than other chemotherapy drugs that have been in use for the last 40 years. Medical researchers have found positive results when using extracts of the plant for treating ovarian and breast cancer. The white bat flower also contains anti-cancer and other medicinal properties, such as treating hypertension.
The black bat flower resembles a bat in appearance, but it certainly cannot take flight or colonize a cave. Yet, as we have seen, this curious flower—like a bat—possesses power, mystery, and a rare beauty.
Paul Hormick, author of the environmental newsletter The Green Dispatch, has spent the last 22 years writing about music, food, and the environment.
Bat Gardens
Bats are an important part of a functioning ecosystem, and with natural habitats in decline they need our help now more than ever. You can welcome bats in your very own backyard by providing food, water, and shelter – creating bat habitat in even the smallest of spaces. In return, insectivorous bats will eat many of your unwanted yard and garden pests. Plus, their nightly displays of aerial acrobatics are fascinating to observe.
About 70 percent of all bat species eat insects, so increasing the number of insects around your home will help bats.
Learn more about how to attract bats to your backyard.
