On a meandering trip back from the coast recently I stopped at the library in Fair Bluff, NC, and popped out of the car for a minute to stretch my legs. There’s a railroad track just across from the library, and because I can never pass up a chance to scope out the wild plants along the tracks, I went that way first.
Something dark purple amid the tiny, pale wildflowers there caught my eye. Dozens of clumps were scattered along the tracks.
A few of the clumps were more magenta than purple.
I’m not sure if any of these are native or whether they’ve naturalized here, but I enjoyed seeing them.
The ornamental value of Stewartia malacodendron has been described by authors of gardening and botanical literature for at least 200 years. William Bartram in his Travels through North and South Carolina, Georgia, East and West Florida (1791) mentioned the plant several times. Near Savannah, Georgia, he wrote of “this ancient sublime forest,” which besides Stewartia malacodendron, included Cornus florida, Halesia, Aesculus pavia, Sambucus, and Callicarpa, among others.
Even then the forest was giving way to development, but conservation was not yet a concern. Bartram wrote that the forest was “frequently intersected with extensive avenues, vistas and green lawns, opening to extensive savannas and far distant Rice plantations,” and that it “agreeably employs the imagination, and captivates the senses by scenes of magnificence and grandeur.” 
One hundred and seventy three years after Bartram, Elizabeth Lawrence wrote of a special trip to see Stewartia malacodendron at the North Carolina coast. Her host Miss Kate took them, after many miles of driving, to some woods that looked “impenetrable,” but then “parted some sweetgum branches and walked into the underbrush as easily as if she had opened a door and entered a country parlor.” Ms. Lawrence had less grace than her host in that situation, and stumbled, grumbled, and lost a few hairpins along the way.
The indignities must have been worthwhile, because Ms. Lawrence recalled the visit ten years after the experience: Eventually, “she [Miss Kate] stopped on the edge of a deep ravine. At the bottom of it a sluggish stream, fed by an old spring, ran through a carpet of fern, and the slope between was covered with a thicket of stewartias. Standing there above them we looked down on the flowers, and that is the way they should be seen—from above, with light coming through many leaves before it reaches the ivory cups that seem to hold the sweet mystery of the woods.”
In June of 1964 Ms. Lawrence wondered whether “the place has been cut up into building lots, or whether a superhighway runs through the ravine.” She fondly remembered how she had, “looked down on those white flowers growing gently among the green leaves.” 
More recently Gil Nelson and Larry Mellichamp have favorably reviewed Stewartia malacodendron in their books.
Dr. Nelson: “The flowers are about three inches wide when fully expanded, making them appear inordinately large against the 2–4-inch leaves. The blossoms are composed of five crinkled petals that start out pure white but change to creamy or yellowish white by maturity. A mass of deep purplish or burgundy-red stamens decorates the center of the blossom, lending a regal air to the flower.” 
Dr. Mellichamp: “Silky camellia is one of the most wonderful year-round trees I have grown. It’s also one of the most difficult. […] In bloom, it’s breathtaking, with dozens of gorgeous white flowers well displayed on the sweeping leafy branches.” He suggests growing the plant in moist, well drained soil, and never letting it dry out until well established. 
The rewards must be worth any extra attention Stewartia malacodendron requires as it’s getting settled into your garden. Mike Dirr is reported to have said about the silky camellia, “It’s every gardeners dream plant, like the finest piece of art or sculpture.” 
This pretty volunteer showed up in my garden one day. I noticed sulphur butterflies seemed to like it too, and it turns out that it is a host plant for them. What I didn’t want to know is that it is considered by some to be one of the world’s worst weeds. In America, in particular, it is controlled with herbicides because it competes for resources with agricultural crops, and it carries Asian soybean rust disease as well. 
In Asia and Africa it is more highly regarded and is often used as food or medicine. In the Sudan, leaves are fermented and then dried and eaten as a source of protein. 
In India the leaves and seeds are considered laxative, anthelmintic, ophthalmic, cardiotonic and expectorant. The leaves and seeds are used for ringworm, flatulence, colic, dyspepsia, constipation, cough, bronchitis, and cardiac disorders, among other things. 
One study  determined that extracts of S. obtusifolia demonstrated a broad-spectrum of activity against both gram-positive and gram-negative bacteria and fungi, which the authors concluded may confirm its use in traditional medicine.
Caterpillars have nearly denuded the plant in my garden at least a couple of times, but there are several long seed pods still attached. They look a lot like haricot verts. I’ll save them and figure out what to do with them later. They’ve been roasted and used as a coffee substitute in some places …maybe that.
 Larry Steckel, “Sicklepod,” Extension.tennessee.edu/publications/Documents/W125.pdf, accessed November 7, 2016.
 Steven Foster and Yue Chongxi, Herbal Emissaries: Bringing Chinese Herbs to the West, Healing Arts Press, 1992, pp. 311–317.
 Pankaj Oudhia, “Charota or Chakad,” Hort.purdue.edu/newcrop/CropFactSheets/cassia.html, accessed November 6, 2016.
 Doughari, El-mahmood, A. M. and Tyoyina, I.”Antimicrobial activity of leaf extracts of Senna obtusifolia (L),” www.academicjournals.org/article/article1380814322_Doughari%20et%20al.pdf, accessed November 6, 2016.