What Is Rhubarb? Plus, How to Cook It.
You know it's instrumental to making strawberry rhubarb pie, but what is rhubarb—and can it do more than make tasty desserts?
When rhubarb starts showing up at the farmers market, it’s a surefire sign that spring has sprung. This tasty treat is the star of our favorite rhubarb recipes for spring, but most of us don’t have any idea what rhubarb actually is.
That’s OK; you’re not alone. We’ve got the details on this sweet-tart treat, including how to cook it.
What Is Rhubarb?
Rhubarb is a perennial plant that grows well in cool climates. The stalks are edible, but it’s sometimes planted as an ornamental plant because of its beautiful, vibrant red stalks and wide green leaves. Consumed raw, rhubarb has an intensely tart flavor that’s not generally liked. But toss it with sugar and bake it into cake, pie, shortbread or jam, and rhubarb’s bitterness fades and becomes delicious.
While it’s most commonly used in combination with other fruits to make sweet treats, rhubarb has several savory applications. Add it to salsa, use it to make chutney or enjoy it as a marinade for meat. If you need inspiration, check out our collection of savory rhubarb recipes.
Learn the difference between red vs. green rhubarb.
Is Rhubarb a Fruit or a Vegetable?
We already know the line between fruits and vegetables is blurry from the tomato debate. But rhubarb is a bit of an interesting case. Botanically, a fruit contains seeds and vegetables consist of leaves, stalks and roots. That definitely makes rhubarb a vegetable, but the U.S. Customs Court legally classified rhubarb as a fruit in 1947. Since it is most often used to make sweet desserts (like other fruits), they deemed that importers shouldn’t have to pay the higher vegetable tax on the stalks.
Like most fruits and vegetables, rhubarb is packed with health benefits, too.
Is Rhubarb Poisonous?
Rhubarb stalks are safe to eat, but the leaves contain a compound called oxalic acid, which is toxic to both humans and animals. The most common symptoms of oxalic acid poisoning are stomach pain, nausea, vomiting and a burning or painful sensation in the throat or mouth.
That sounds terrible, but we’re not that worried. You’d have to eat several pounds of rhubarb leaves to reach a toxic level.
When Is Rhubarb in Season?
Rhubarb grows best in cool weather below 75° F, so it’s widely available during the springtime. You’ll find it in most areas beginning in April or May, although some regions tolerate rhubarb growth throughout the summer. It is possible to grow rhubarb indoors or in a hothouse, so don’t be surprised if you find it as early as January!
Learn how to grow rhubarb in your garden!
How to Harvest or Choose Rhubarb
If you’re harvesting rhubarb from the plant, it’s important to choose stalks that are firm and upright. Frost can cause the toxic oxalic acid from the leaves to migrate into the stalks, so avoid anything that’s flimsy or soft. Dark red rhubarb is sweeter and more flavorful, but the green stalks are edible, too.
To pick rhubarb, put away your garden shears! Grasp firm stalks and pull and twist to harvest. Stalks that are ready to eat should pull away easily; if you’re having a hard time pulling, leave that stalk to grow some more. Remove the leaves and wash the rhubarb well to remove any excess dirt.
At the grocery store or farmers market, look for firm, shiny stalks without any blemishes. If the rhubarb has the leaves attached, look for leaves that look fresh and haven’t wilted.
What Does Rhubarb Taste Like?
Rhubarb has an extremely tart flavor that many find unpleasant. It’s crunchy like celery when raw, but it becomes soft and after it’s cooked. The sour flavor does mellow a little when cooked, but rhubarb is almost always mixed with sugar to counteract the lip-puckering taste.
How Do You Store Rhubarb?
After harvesting, rhubarb stalks should be stored in the refrigerator. The ends dry out easily, so it’s best to wrap rhubarb in a towel or place it in a reusable produce bag. Our favorite way to store rhubarb is like celery: loosely wrapped in aluminum foil. Just make sure not to wrap the ends too tightly. Rhubarb should last about two weeks in the refrigerator when properly stored.
If you can’t use it all, freeze the rhubarb and eat it all year long. First, slice the stalks into one- to two-inch pieces. It can be frozen raw, or you can blanch the rhubarb in boiling water for one minute to set the color, dunking it in an ice bath to stop the cooking process. Either way, pat the pieces dry and place them in a single layer on a wax paper-lined baking sheet. Freeze the rhubarb for four hours before transferring the pieces to a freezer bag. Frozen rhubarb should last about a year in the freezer.
How to Cook Rhubarb
After trimming off the leaves, you’re ready to get cooking with rhubarb. If the stalks have any small blemishes, you can remove them with a vegetable peeler. From there, you have some options. Here are a few of our favorite ways to cook rhubarb.
Cut the stalks into 2-inch pieces. Then, julienne the pieces into matchsticks and toss them with red wine vinegar and a pinch of salt and sugar. After marinating for a few minutes, add the quickly pickled rhubarb to fresh salads, slaws or use as a pickle for sandwiches.
Cut the rhubarb into 1-inch pieces. Simmer the chopped rhubarb in a small saucepan over medium-low heat with water and sugar (for every 3 cups of rhubarb, add 1 tablespoon water and 1/2 cup sugar). After 15 minutes, let the mixture cool. Pour the stewed rhubarb over ice cream, cakes or use it as a syrup for pancakes or waffles.
Toss chopped rhubarb with sugar (about 1/2 cup for every 3 cups of rhubarb). Bake it in a 350°F oven for 15 to 20 minutes, until it’s soft and tender. Puree the baked rhubarb and use it to make homemade soda, add it to boozy margaritas or turn it into ice cream.