Posted on Aug 30, 2012 by Michael Parkey
Yesterday evening an event occurred in my garden that happens several times each year, and which I am always eager to see. It is the mass flowering of my jimson weed, Datura wrightii.
Jimson weed actually has a very long bloom season, from April until October. But occasionally conditions occur that produces an especially spectacular show. A long spell of hot weather in which the mature plants slow down, followed by heavy rain predictably will cause the simultaneous bloom of hundreds of flowers. And these are not tiny little things, but huge white trumpets six to eight inches in diameter.
For several days before you can see the long, greenish-white buds standing erect on the plants. Each unopened flower is twisted shut, the spiral clearly visible at the end. After sunset when dusk deepens into darkness, all the flowers open within 15 minutes of each other. The opening of an individual flower actually happens quickly enough to see the movement. The trumpet expands and unfurls until a spring tension builds up, then it pops open fast enough to cause the whole branch to tremble. Last night this happened at about 8 PM.
As soon as the flowers open, you can smell their sweet but lemony scent. And so can their natural pollinator, a fast-flying hawk moth big enough to be mistaken for a humming bird out past her bed time.
The flowers remain open all night and into the next morning. As soon as it is light, the honey bees have their turn, mobbing the flowers with a high, whining buzz. On a cool, rainy day the flowers might stay open until sunset. On a hot day like today, they wilt by 10 AM.
Datura wrightii has numerous common names in English: jimson weed, loco weed, devil’s weed, Indian apple, angel trumpets, and sacred datura. There are literally hundreds in other languages, including all the native American tongues from Central America to New England. All species in this genus have a rich ethnobotanical heritage because the plants are loaded with trophane alkaloids; compounds which are fatal to mammals in surprisingly small doses. Do not eat this plant! In slightly smaller doses, the alkaloids cause hallucinations and delirium which can last for days, leading to their ritual use by many cultures. In even smaller doses, the plant can relieve the symptoms of severe, acute asthma.
But jimson weed is not a plant to toy with. In a famous incident, British soldiers were sent to put down a rebellion in the Jamestown colony of pre-revolutionary Virginia. The colonists fed the soldiers cooked Datura greens. The soldiers spent the next ten days in alkaloid-induced psychosis; they ran naked through the colony and smeared themselves with their own excrement. Not my idea of a fun party! The name “jimson” is actually a corruption of “Jamestown”.
But we do have a little party whenever there is a datura night in our garden. We get out the lawn chairs, watch the flowers open, and try to get a good look at the hawk moths even though they fly so fast they are just a blur.