Japanese Knotweed Harvest and Recipes

I love this hated weed in the spring. It is easy to harvest, hard to mix up with anything else, and tastes great in so many recipes.

We brought it here to the US from Japan in the late 1800’s because rich folks liked the way it looked as an ornamental on their estates. Now we are suffering because is grows in thick clumps and takes over where native vegetation used to thrive, AND it lets erosion happen right underneath it while it towers over head. It is hard to kill. It’s thriving in most of the states in the US. So let’s cut it down while it’s tender and tasty and eat it as a way to get rid of some of it. It’s a slow method but at least we are doing something. And, when it’s cut down, it sprouts back giving you another flush of tender shoots extending the short harvest season.

I find a stand of young knotweed shoots that look like the picture below and pop off the stalks near the base. You should hear a distinct pop when the shoot breaks off signaling it’s ready to pick. If it’s too old, it will just bend. Forget those. They are too tough and stringy to use. It’s possible to gather enough knotweed to be up to your eyeballs if you are not careful. Then, you have the problem of disposing of it. Don’t just throw it in the trash. If you happen to gather some roots, it will start to grow right there in your trash can and out the door before you throw it out. OK, maybe an exaggeration, but it will grow wherever it lands, so be careful. I’m also careful not to harvest it along roads where car exhaust lands on it all day.

To prepare the stalks for cooking, I fill the sink with cool water, drop the stalks in, and then one by one, wash them, take the leaves off and line them up on a cutting board for cutting in batches. It’s slimy. When I have a cutting board full, I cut them in 1 inch sections and throw them in a large pot. Once here, it’s possible to go many different directions. Muffins, breads, soup, pies, jelly, or simple syrup. I make sure to stock up on this simple syrup. It’s a kid pleaser as a lemonade or seltzer. It is one of my favorite cocktail simple syrups. The flavor is unique yet reminiscent of lemons.

Japanese Knotweed Simple Syrup

• 4 cups cleaned and prepared knotweed stalks chopped into 1 inch sections
• 4 cups water
• 4 cups white sugar
• 1/2 lemon fresh squeezed juice strained through jelly bag

Bring knotweed and water to a boil in a medium large pot. Cook simmering for 10 minutes or until the stalks fall apart easily. Strain the mixture through a jelly bag several times. The liquid is pale pink and cloudy no matter how many times you filter it. *Save the pulp for another recipe by freezing it. Measure and return the liquid to a clean pot. Add the sugar in equal amounts by volume to the liquid. Four cups is an approximation. It depends on how much liquid you leave in the pulp. Stir the liquid and sugar over medium low heat until the sugar dissolves and the liquid boils slowly for about a minute. Add the lemon juice to enhance the lemony flavor if you wish. I filter the fresh squeezed juice through the jelly bag just out of habit, but the cloudy nature of the syrup doesn’t warrant that. At this point, you may can this syrup for a long shelf life using standard hot water bath canning procedures for 10 minutes. https://www.healthycanning.com/water-bath-canning-step-by-step Or, you can keep it in glass jars with lids in your fridge for immediate use. I have had this syrup last over 6 months unopened in my fridge. I do not guarantee this though. This syrup is one of my favorites for general gifts and use because the taste is guaranteed to please.

I usually have enough knotweed juice to make more liquid than I need for the simple syrup. I will often put it in the fridge until I can turn it into jelly in a day or two. Here is the recipe for jelly. It’s a crowd pleaser too.

Knotweed Jelly Recipe

• 2 cups knotweed juice prepared as above before adding the sugar
• 1.75 oz. powdered pectin
• 2 cups of sugar

Pour the knotweed juice into a clean medium pot. Bring to a simmer. Add the pectin and stir until it is completely dissolved. Bring the mixture to a boil while stirring constantly. Stir in the sugar and bring the liquid to a full boil. Boil hard for 1 minute while stirring. Pour into your clean pre-prepared canning jars and top with prepared lids. This makes about 6 or 7 four oz. jars. Use standard hot water bath canning methods, boiling for 10 minutes. https://www.healthycanning.com/water-bath-canning-step-by-step I will often double this recipe and it still works well.

Ellen Zachos’ Knotweed Cupcakes with Ann’s twists

Ellen Zachos wrote this wonderful book called “The Forager’s Pantry” which is full of recipes. I have trouble following recipes. This is the result of that problem. But the outcome was fabulous so the original recipe had to be too. This yields about a dozen dense little cupcakes that pack a wonderful complexity of flavors. You will need the *Knotweed Puree (find asterisk for that info) and the Knotweed Simple Syrup described above. The Spicebush berries are always in my freezer frozen from my harvest the previous fall. They are a mainstay in my spices, but you can use clove, ginger, cinnamon or your other favorite cake spice instead. IF you haven’t a clue what I’m talking about, and you are adventuresome, next fall, you MUST gather the Spicebush (Lindera benzoin) red berries and dry and freeze them for Appalachian Allspice – my favorite local spice.

• 6 Tbs. knotweed puree (sweetened to taste)
• 2 Tbs. butter, softened
• 1/2 cup sugar
• 2 Tbs plain full fat yogurt
• 1 egg
• 1/2 tsp vanilla extract
• 3/4 cup all-purpose flour
• 1/2 tsp baking powder
• pinch of salt

Prepare the knotweed puree. My knotweed was frozen before being pureed and unsweetened so I thawed it, pureed it and sweetened it to about applesauce sweetness. I could have gone with less sugar and been fine.

Prepare the cupcakes. Preheat oven to 350^oF. Prepare a cupcake tin for a dozen cupcakes by either using cupcake liners or greasing each cup in the pan thoroughly. Cream the softened butter with the sugar until pale and evenly smooth. Beat in the knotweed puree, yogurt, egg, and vanilla. Combine the flour, baking powder, and salt in a separate bowl, mixing thoroughly. Add the dry ingredients to the wet ingredients and mix until just combined. Pour into the cupcake pan filling each cup 3/4 full. Distribute any remaining batter evenly between the cups. Bake about 20 minutes or until toothpick comes out clean. Cool for 5-10 minutes and remove cupcakes from the pan. Cool completely on a wire rack before icing.

Prepare the Knotweed Buttercream Icing for 12 cupcakes

• 1/2 lb. confectioners’ sugar
• 1/4 cup unsalted butter
• 1/2 tsp vanilla extract
• 2 Tbs milk
• 2 Tbs Knotweed Simple Syrup (see recipe above)
• 1/2 tsp ground Spicebush berries (optional)

Mix all ingredients and whip icing thoroughly and rigorously until it holds a peak. If you’ve whipped it and it still isn’t stiff, add confectioner’s sugar little by little until the peaks no longer flop over. Ice your cupcakes and decorate with sprinkles of crushed or ground Spicebush berries (or cinnamon, ginger, or your favorite cake spice or nothing). Enjoy and tell me what you think.