May we suggest that you celebrate it on April 22 by dining on an invasive plant?
Photography by Marie Viljoen, except where noted.
Japanese knotweed (Polygonum cuspidatum, and also known as Fallopia japonica). You may not sell your property there if Japanese knotweed grows on it.
Japanese Knotweed
Like so many other problem plants, Japanese knotweed was imported (from eastern Asia) as a garden ornamental, before escaping. But this aggressive member of the buckwheat family ran botanical riot in habitats where it had no natural enemies.
The federal Environmental Protection Agency currently has little negative to say, although in 2015 California’s EPA listed glyphosate as a human carcinogen.
But until the psyllids start sucking full-time, there is another way to tame this floral thug and it is mechanical. Digging up knotweed with a back hoe looks impressive, but is ineffective: knotweed can regrow from a just a small piece of left-behind root.
Photograph by Steven Schwarz.
On his acreage on the banks of the Delaware River in Pennsylvania, Steven Schwarz, chief forager at Delaware Valley Ramps, and founder of the Upper Delaware BioBlitz, employs what he calls “the Sampson Approach,” in order to avoid the use of chemicals on the Japanese knotweed that chokes the river edges.
“So far I don’t think I’m winning but I’m not losing either, and I have contained the worst patches from spreading.” In one of these patches prized ostrich ferns – a source of edible fiddleheads – seem to be competing with the knotweed, because they now have access to sunlight.
As the world becomes digitally connected, word is spreading about the culinary potential of this despised plant.
The choice edible part of Japanese knotweed is its young shoot, which resembles an asparagus spear. These tart stems are stuffed with resveratrol, the antioxidant polyphenol touted for its anti-inflammatory effect.
To harvest the shoots, choose a spot where the previous season’s old canes (dry, brown, and hollow) stand untidily. If there are none, the chances are good that the clump was sprayed the year before.
When the shoots are very tender, you can use the whole stem. Peel tougher stems and discard the joints between each hollow section, as they can be tough.
Pickle the stems, using your favorite recipe (I use 50/50 vinegar and water, adding sugar, salt, and allspice berries).
Or cut them thinly and scatter across creamy burrata or mozzarella, sliver them into salads and toss them into hummus.
Cooked, the stalks are mellower and soft, and reminiscent of sorrel.
After the stems have matured, the young unfurling leaf tips are still good to eat, with more crunch than the melty, cooked stems. Sauté them briefly to add to omelets, to accompany spring meatballs, as a green stew with fava beans, or as a tart side to a rich main dish.
Japanese knotweed adds the citric note usually provided by lemon juice. *Prepare the Japanese knotweed stalks by cutting them at each joint and discarding the joints (they are tough). Add the knotweed, tahini, field garlic or garlic cloves, and the salt.
Japanese Knotweed Hummus