(No, I will “knot” be sick of these puns any time soon!)
I went back to the Japanese knotweed (Polygonum cuspidatum) patch earlier this week to check the harvest. Its slow but inevitable spread shows clearly in this photo, where the new shoots are breaching the ground several feet away from last year’s stalks.
The fattest shoots come from well-established root systems. I guess they could be called “crowns”, like you would say for rhubarb or asparagus. The shoots that from newer roots, where the knotweed reaches inexorably towards its next victim, tend to be thinner.
Whatever the thickness, the best stage for harvesting appears to be twelve inches or less. Bigger than that, and the shoots may need to be peeled before eating as the skin gets tougher.
I harvested about a pound to try. There was much more than this, but I didn’t want to bring a bunch home in case it out to be unpleasant eating after all. (Like the hairy bittercress from a few weeks ago!) As I said last week, I tried to leave us much discarded leaf bits and stem tips there, on the already contaminated site.
Most sources compare the flavor of knotweed to rhubarb. To be honest, I am not overly familiar with the taste of rhubarb. I planted some last year as part of my adventures in edible landscaping, but I was concerned about harvesting too many stalks from the young plants… and I was never sure what to do with the ones I did collect! This year at a minimum I plan to try a pie, and maybe a rhubarb fizz. But I digress. I cannot tell you if knotweed does or does not taste like rhubarb because I don’t actually know!
First thing’s first: I had to try it raw, just because I could. I learned that I don’t care for the taste of knotweed raw, although it is edible uncooked.
Peeling was a pain, I presume because the pieces I collected were all young enough to that they didn’t need the extra treatment. The bits of flesh I managed to scrape off gummed up my peeler and rendered it useless.
All the random leftover vegetable bits got shoved in a plastic bag to go in the trash, which is unlike me. I compost anything vaguely likely to decompose. Even the cardboard centers of paper towel rolls… in addition to the used paper towels themselves, as long as they aren’t covered in meat or grease or cleaning chemicals. But I refuse to allow a single scrap of the knotweed back into the wild. Especially my wild.
So far I have sampled cooked knotweed two different ways, both as vegetable sides. The first – and so far, my favorite – was sauteed in sesame oil with a touch of soy sauce. Maybe the knotweed favored ingredients similar to its ancestral homeland. For whatever reason, it was ridiculously delicious. Tart, but not unpleasantly so.
The second time, I sauteed the knotweed gently in butter, then sprinkled it with grated Parmesan cheese once it finished cooking. This was OK, but not as good as the sesame oil/soy sauce treatment.
Bits of the knotweed also cooked a little too much. I personally don’t care for the texture of overcooked knotweed. A pleasant way to describe it would be to say it “melts”. It disintegrates. It becomes, dare I say, mushy. Some authors find this appealing; not I. (Knot I?)
Also, my kids – the brave youth who taunted each other into trying the hairy bittercress soup – refused to even touch the knotweed.
Since I have such a large supply of knotweed available, I am hunting for more recipes. It seems wasteful not to take advantage of so much wild edible food. What else to do with it? Pickles seem like a popular option online.
I have a hard time imagining it in a rhubarb-strawberry pie, or a fool, or any other sweet dish. Except maybe jam, where its texture would be a non-issue. I love Alan Bergo’s work, although I feel like a knotweed “mousse” might be too fussy (particularly with my family). But I like the idea of freezing sweetened knotweed puree for later, if I can identify other uses for it.
Maybe next year I will try knotweed wine, but right now it seems like more commitment than I want in a recipe. On the other hand, an infused vodka or liqueur sounds right up my alley. Especially since it has been almost a week since I visited the patch – no telling how much bigger the shoots will be. Soaking them in vodka would be a great way to use the larger, tougher stalks.
Any other suggestions as to the best way to eat Japanese knotweed? What other invasive species do you enjoy?