|The leaves on this Japanese Knotweed are just beginning to unfurl.|
The first time I saw it, I'll admit, I was somewhat taken with what seemed to be a wonderfully elegant perennial. It's leaves were large green hearts, it's blossoms were held in pendant, creamy sprays at the tip of each stalk, and the stalks curved ever so slightly with the weight of the blossoms. In the forest garden where they stood, next to black bamboo and framing the ocean just so, it seemed as though they had been planted with an expert eye. I marveled at how I had never noticed them there, and how it was almost as if they had appeared out of nowhere. It wasn't long before I started noticing the same creamy sprays of flowers in a lot of other places, even on roadsides. I thought it must be a really popular plant, and was surprised that I hadn't already known about it. The nurseries I frequented didn't sell it, though I thought they should. How wrong I was.
It came upon me how wrong I was while I was listening to CBC radio one day as I weeded the garden (a staple for many Canadians who work with their hands, I think). I was listening very closely as the votes were coming in for Canada's most invasive weeds. Listener after listener called in to tell stories about weeds growing through pavement, weeds resisting all kinds of sharp tools, and weeds that have caused tough gardeners to ultimately surrender. As I listened, I realized many of the callers voted for a weed that was a dead ringer for the "elegant perennial" I had noticed. It was commonly called Japanese Knotweed, and it came out on top as Canada's most hated weed that day, over crabgrass, thistle and dandelions.
Needless to say, I began chipping away at that patch of knotweed in the woods, but my efforts to dig it up were only matched by the speediness of the smallest rhizomes to put on a spurt of growth. Japanese Knotweed (Polygonum cuspidatum) is tolerant of most any soil or growing conditions. It grows fast, and can colonize abandoned spaces and fragile ecosystems alike. Since its introduction to the United States as an ornamental plant in 1910, it has made its way out of cultivation and onto invasive species lists of many states. My attitude toward the plant has changed in the same way.
Seeing as the stalks resembled asparagus so much in the way they looked, I steamed them to serve with fresh pasta, trout and peas. To my surprise, the taste was not at all like asparagus. They're the most similar thing to rhubarb I've ever tasted. They're tangy, fibrous, and slightly sweet, and the leftovers I have would be a great addition to quickbread or muffins. (New England wild edibles guru Russ Cohen recommends combining them with seasonal strawberries to make pie, and The Three Foragers tried using it to make wine.) Eating this weed is all in all a pleasant experience. Not only is knotweed pleasant to taste, but it's chalk-full of resveratrol, the antioxidant in grapes and wine that is becoming quite favorable. (For this reason, the knotweed is now being cultivated in China.)
Other invasive species I'd like to relish this season? Yes, plenty! I've got my eye out for garlic mustard, dandelion greens, European barberries, ramp, chickweed, and any other delectable edibles that dare to cross me.