By Vicky Barney, Routt County Master Gardener. Vicky gardens for wildlife and is a member of the Master Gardener Class of 2011.
A native plant new to me is growing in my garden: Western spiderwort (Tradescantia occidentalis). Recommended by my friend and local botanist Karen Vail, the plant has unusual habits that complement the neighboring plants. It has become my favorite in the garden, at least for now.
A variety of spiderworts are native to the North American plains. According to the Lady Bird Johnson Wildflower Center’s Native Plant Database, there are 33 in the family, with 4 native to Colorado. My Colorado wildflower guides list only Western spiderwort (also called Prairie spiderwort), which grows in the plains and foothills of eastern Colorado. The spiderwort name may have originated by the spider leg appearance of the foliage or because it was once used to treat spider bites. “Wort” is the Old English word for plant.
There are a number of cultivated varieties with names like Spider Lily, Purple Heart, and Cow Slobber – really! Spiderworts from tropical climates have been cultivated as houseplants as well, with names like Wandering Dude and Moses-in-the–cradle. The houseplants are easy to grow but may have toxic properties.
My spiderworts arrived last summer as leggy plants sprawling out of tiny containers. They were bedraggled, with foot tall stems bent over by the weight of spent buds. From research, I learned the plants would grow in untidy clumps and might need maintenance like staking, deadheading, and cutting back. They might also be invasive. It sounded like a lot of work for flowers that last for only a single morning. The research, though, was about cultivated varieties, not about my natives.
My spiderwort plants have been a treat to observe. Planted in light shade with drip irrigation and with no staking, every plant has grown upright over 2 feet tall. Beautiful triangular flowers appear in the morning and last until mid-afternoon. The blue petals then disappear back into the original bud, now spent. New blooms appear the following morning, a process that may go on for two months.
To date, I am a big fan of spiderwort. Plants may suffer from foliar decline later in the summer but can be cut down once they quit blooming. They also may get unruly looking (read: weedy) if they reseed, but for now, they are a wonderful addition to my garden.
For more information, please see CSU Extension’s Fact Sheet 7-242: Native herbaceous perennials for Colorado Landscapes (https://extension.colostate.edu/docs/pubs/garden/07242.pdf).