Growing rhubarb in Washington State: A tangy tradition with deep roots

If you have ever spotted those massive leafy greens unfurling like umbrellas over crimson stalks in a backyard garden, you have likely seen rhubarb. In Washington State, rhubarb is not just a springtime staple; it's a legacy crop with roots that stretch back generations, thriving in the cool, moist climate that makes our region one of the nation's top producers.

According to the article Farm Facts, Washington State leads the nation in rhubarb production, accounting for nearly 90% of the U.S. commercial rhubarb crop. Most of that is grown in Pierce County, particularly near the town of Sumner, where the soil is rich and the rainfall generous. Rhubarb thrives here, preferring the damp springs and moderate summer temperatures of Western Washington.

According to the Washington State Department of Agriculture, rhubarb contributes more than $10 million to the state's economy each year, with thousands of acres in production. Both organic and conventional growers serve markets across the country, with a growing interest in locally sourced rhubarb for culinary and health products.

Thanks to local growers, Sumner has even earned the title "Rhubarb Pie Capital of the World," according to the City of Sumner website. It's no surprise that the town hosts Rhubarb Days every summer, a festival featuring rhubarb-themed contests, music, and, of course, pies.

Whether you are a seasoned gardener or just starting, rhubarb is a hardy perennial that is surprisingly easy to grow in Washington. Plant rhubarb crowns in early spring or fall when the ground is workable. Well-drained, fertile soil with plenty of organic matter is key. Rhubarb does not tolerate soggy roots. Give each plant three to four feet of space to stretch out, with plenty of sun. It will tolerate partial shade in hotter microclimates. A permaculture bed is ideal. Rhubarb likes consistent moisture, especially during dry summer spells. Do not harvest the first year; let the plant establish. In the second year, harvest sparingly by twisting at the base of each stalk. By the third year, you can harvest stalks when they are 12 to 18 inches long, leaving the center stalks intact to support the plant. Do not eat the leaves as they contain high concentrations of oxalic acid and are toxic to humans and pets.

Once settled, rhubarb can produce for up to 15 years, becoming more robust each season. In colder parts of the state, a winter mulch can protect the crowns. In western Washington, rainfall usually provides enough moisture, though drainage is key.

Rhubarb packs a nutritional punch and is low in calories, with about 26 calories per cup, making it a guilt-free treat. Rhubarb is rich in antioxidants, especially anthocyanins, the pigments that give red stalks their color. As a reliable source of fiber, it helps to regulate the digestive system. It is also full of Vitamin K, which is essential for bone health and blood clotting. Lastly, rhubarb is a source of calcium and vitamin C, which are essential for immunity and skeletal strength.

Its tart flavor is due to malic acid and oxalic acid, which are naturally occurring compounds found in small amounts in rhubarb stalks and also in green apples and spinach. While rhubarb is technically a vegetable because it doesn't have seeds, the key characteristic of a fruit, it still takes on the role of a fruit in many dishes, causing many to mistake it for one. From jams and chutney to BBQ sauce and desserts, rhubarb fills a variety of niches at the table. Here is a simple and satisfying way to enjoy the first harvest of the season.

Classic Rhubarb Crisp

Ingredients:

4 cups chopped fresh rhubarb

1 cup granulated sugar

2 tablespoons cornstarch

1 tsp vanilla extract

1 cup old-fashioned oats

1/2 cup all-purpose flour

1/2 cup brown sugar

1/2 tsp cinnamon

½ tsp cardamon

1/2 cup cold butter, cubed

Instructions:

Preheat oven to 375F. In a mixing bowl, combine rhubarb, sugar, cornstarch, and vanilla. Pour into a greased 9x9-inch baking dish. In a separate bowl, mix oats, flour, brown sugar, and cinnamon. Cut in butter with a pastry cutter or fork until crumbly. Sprinkle this topping evenly over the rhubarb. Bake for 35–40 minutes, or until the topping is golden and the filling is bubbly. Let cool slightly before serving. Best enjoyed warm with vanilla ice cream or a dollop of whipped cream.

Rhubarb's tart taste, easy cultivation, and deep connection to Washington's agricultural heritage make it more than just a pie ingredient-it is a plant that tells a story. Whether you grow it in a backyard plot, buy it at your local farmer's market, or enjoy it at a summer festival, rhubarb deserves a spot on your seasonal menu.