…that is the question. The answer is: to eat, of course!
We first asked this culinary question in our Late Spring 2008 newsletter. When we saw a recent article in Bon Appetit magazine about invasive Japanese knotweed’s growing popularity (no pun intended) with upscale restaurants, we thought it would be a good time to repeat this article.
Japanese knotweed, or Polygonum cuspidatum, is a stout-stalked perennial herb, sometimes reaching 10 feet in length that loves to grow in neglected places. Once established, watch out! as it grows and spreads very quickly. It is on the invasive species list in Washington as well as many other states. One tasty solution to its invasiveness is found in the recipe below.
Using last year’s stalks as the sentinels to guide you, harvest the top 4-6 inches of knee-high new shoots. Don’t delay. As they become older, the stalks will become be too fibrous to enjoy. They can be steamed and served like a sour asparagus, creamed into soup, or made into Karen’s personal favorite, knotweed crunch.
For identifying characteristics, please use a reputable plant identification guide. One of our favorites here in the northwest is Plants of the Pacific Northwest Coast by Pojar and MacKinnon. As always, be safe, know what you are harvesting, and be certain to harvest in areas that have not been sprayed. Because this is a very invasive species, be careful not to disturb the roots or do anything else that might spread the plant. Most of all, remember that if you can’t beat ’em, eat ’em!
The crust and topping:
Mix ingredients and spread half into a 9″ x 13″ pan. Reserve the other half for topping.
- 1 cup whole wheat flour
- 1 cup oats
- 1 cup brown sugar
- ½ cup butter
Add 8 cups chopped knotweed and spread over crust.
In a medium sauce pan combine:
- 1 cup water
- ¾ cup sugar or honey
- 3 tbsp cornstarch
- pinch of salt
Bring to boil and cook until thickened. Remove from heat and add 1 tsp vanilla. Pour over chopped knotweed. Sprinkle on remaining topping. Bake at 350 degrees for 40 minutes. Enjoy!