What is Rhubarb?16 Benefits, Side Effects & How to Grow it

When spring arrives, and gardens come back to life, one of the first plants to emerge is a bold, red-stalked vegetable that most people mistake for a fruit — rhubarb. Whether you’ve seen it peeking out of a garden bed or spotted it on a dessert menu, rhubarb has been a staple in kitchens.

Despite its tart flavor and somewhat intimidating appearance, rhubarb is a nutritional powerhouse packed with vitamins, minerals, antioxidants, and fiber. And while it’s most commonly used in sweet desserts, it has a wide range of culinary and medicinal applications that make it worthy of a permanent spot in your diet.

In this article, we’ll explore everything you need to know about rhubarb — what it is, its types, nutritional profile, 16 powerful health benefits, and side effects to be aware of. Plus, we will also discuss how to grow it at home.

What is Rhubarb?

Botanically speaking, rhubarb (Rheum rhabarbarum) is a vegetable, a member of the Polygonaceae family, which also includes buckwheat and sorrel. However, its culinary application, particularly its tartness and use in desserts like pies, crumbles, and jams, often leads people to categorize it as a fruit. In fact, a 1947 U.S. Customs Court ruling even classified rhubarb as a fruit for tariff purposes! 🍏

Originating from Siberia and China, where it has been cultivated for over 5,000 years, rhubarb was initially prized for its medicinal roots. It wasn’t until the 18th century that its stalks gained popularity in European kitchens, especially after the introduction of sugar made its intense tartness more palatable.

The plant itself is quite striking, featuring large, triangular leaves (which, remember, are toxic!) and thick, fleshy stalks that can range in color from vibrant crimson to pale green, often with streaks of pink. The color of the stalk doesn’t necessarily indicate sweetness or ripeness, but rather the variety of the plant.

Varieties of Rhubarb

There are numerous varieties of rhubarb, each with slightly different characteristics in terms of color, flavor, and harvest time. Some popular ones include:

• ‘Victoria’: A very popular and reliable green-stemmed variety, known for its good yield and strong flavor.
• ‘Crimson Red’/’Cherry Red’: Features beautiful, deep red stalks and a less tart flavor, making it a favorite for desserts.
• ‘Canada Red’: Another red-stalked variety, prized for its sweetness and early harvest.
• ‘Glaskins Perpetual’: A green-stalked variety that is known for being productive and less prone to bolting (going to seed).
• ‘Macdonald’: Offers attractive red stems and is a vigorous grower, excellent for main harvests.

Understanding these varieties can help you choose the best type for your garden or culinary needs.

Nutritional Facts of Rhubarb (Per 100g)

Rhubarb is a low-calorie food that is surprisingly rich in essential vitamins, minerals, and dietary fiber. Here is a breakdown of its nutritional profile:

Note: Values are approximate and may vary depending on the variety and growing conditions.

Despite being very low in calories, rhubarb delivers an impressive array of essential nutrients. It is particularly notable for its Vitamin K content, which exceeds that of many other commonly eaten vegetables.

16 Health Benefits of Rhubarb

Rhubarb isn’t just a tart addition to your favorite dessert — it is a genuinely health-supporting food with a range of well-documented benefits. Here are 12 powerful reasons to add rhubarb to your diet:

1. Digestive Health Champion: Rhubarb’s Fiber Power

One of rhubarb’s standout benefits is its impact on digestive health. The stalks are an excellent source of dietary fiber, both soluble and insoluble. This fiber content is crucial for maintaining a healthy digestive system.

Soluble fiber helps to bulk up stool and can regulate blood sugar levels, while insoluble fiber adds bulk and helps food pass through the digestive tract more efficiently, preventing constipation. This dual action makes rhubarb a fantastic ally for gut regularity.

2. Natural Laxative Properties

Beyond just general fiber, rhubarb contains compounds called anthraquinones, specifically sennosides, which give it natural laxative properties.

These compounds stimulate bowel movements by irritating the colon lining, leading to muscle contractions. This can be particularly helpful for individuals experiencing occasional constipation. However, due to its potent effects, it’s advisable to use rhubarb for this purpose in moderation to avoid dependency or discomfort.

3. Rich in Antioxidants for Cellular Protection

Rhubarb is packed with powerful antioxidants, including polyphenols like anthocyanins (which give red rhubarb its vibrant color) and stilbenoids like resveratrol.

Antioxidants are vital because they neutralize free radicals in the body, which are unstable molecules that can cause oxidative stress and damage to cells. This cellular protection helps reduce the risk of chronic diseases and slows down the aging process.

4. May Support Heart Health

The fiber, antioxidants, and potassium found in rhubarb collectively contribute to heart health. The soluble fiber helps lower LDL (“bad”) cholesterol by binding to it in the digestive tract and facilitating its excretion.

Potassium is essential for maintaining healthy blood pressure levels by counteracting the effects of sodium. Furthermore, the anti-inflammatory properties of its antioxidants can help protect blood vessels from damage, reducing the risk of cardiovascular disease.

5. Bone Strength with Vitamin K and Calcium

While dairy often gets all the credit for bone health, rhubarb is a notable source of vitamin K and calcium. Vitamin K is crucial for bone metabolism and plays a role in bone mineralization. It helps the body produce proteins necessary for healthy bone tissue.

Calcium, of course, is the primary mineral component of bones and teeth, essential for maintaining their structure and strength. Incorporating rhubarb into your diet can be a delicious way to support strong bones.

6. Boosts the Immune System with Vitamin C

Rhubarb contains a decent amount of vitamin C, a well-known immune system booster. Vitamin C is a powerful antioxidant that helps protect immune cells from damage and supports the production of white blood cells, which are critical for fighting off infections. Including vitamin C-rich foods like rhubarb can help your body stay resilient against common illnesses.

7. Potential Anti-Cancer Properties

Emerging research suggests that certain compounds in rhubarb, particularly rhein, emodin, and physcion (types of anthraquinones), may possess anti-cancer properties.

Studies indicate these compounds can induce apoptosis (programmed cell death) in various cancer cell lines and inhibit tumor growth. While more human studies are needed, the preliminary findings are promising and highlight rhubarb’s potential as a chemopreventive agent.

8. Aids in Weight Management

Rhubarb is a fantastic food for weight management due to its low calorie count and high fiber content. A serving of rhubarb offers substantial volume and fiber with very few calories, helping you feel full and satisfied without overeating. The fiber also aids in stabilizing blood sugar, preventing the spikes and crashes that can lead to cravings.

9. Supports Vision Health

Rhubarb contains lutein, an antioxidant known for its benefits to eye health. Lutein accumulates in the retina and helps filter harmful blue light, protecting the eyes from oxidative damage. Regular intake of lutein-rich foods may reduce the risk of age-related macular degeneration and cataracts.

10. Anti-Inflammatory Benefits

The array of antioxidants and phytonutrients in rhubarb contributes to its anti-inflammatory properties. Chronic inflammation is a root cause of many diseases, including heart disease, diabetes, and certain cancers. By helping to reduce inflammation throughout the body, rhubarb can contribute to overall disease prevention and wellness.

11. Blood Sugar Regulation

While rhubarb is often paired with sugar in desserts, the vegetable itself can help regulate blood sugar. Its high fiber content slows down the absorption of sugar into the bloodstream, preventing rapid spikes. Some research also suggests that certain compounds in rhubarb may improve insulin sensitivity, making it a potentially beneficial food for individuals managing or at risk of type 2 diabetes.

12. May Improve Brain Health

The antioxidants in rhubarb, particularly resveratrol, have been linked to improved brain health. Resveratrol is known for its neuroprotective effects, potentially enhancing cognitive function and protecting against neurodegenerative diseases by reducing oxidative stress and inflammation in the brain.

13. Supports Liver Health

Traditional medicine systems have long recognized rhubarb’s role in supporting liver function. Its detoxifying properties, attributed to its anthraquinones and other compounds, may help the liver process toxins more efficiently. Some studies suggest rhubarb extracts can protect the liver from damage and support its regenerative capacity.

14. Skin Health Benefits

The vitamin C and antioxidants in rhubarb are also beneficial for skin health. Vitamin C is crucial for collagen production, which gives skin its elasticity and firmness. Antioxidants protect skin cells from environmental damage and can reduce the signs of aging, promoting a healthier, more radiant complexion.

15. Culinary Versatility

Beyond its health benefits, rhubarb is incredibly versatile in the kitchen. While famous in sweet dishes like pies, crumbles, and jams, it also shines in savory applications. Its tartness can cut through rich flavors, making it an excellent addition to chutneys, sauces for meats, and even salads. This versatility makes it easy to incorporate its health benefits into a wide variety of meals.

16. Traditional Medicinal Uses

Rhubarb has a long and storied history in traditional medicine, particularly in Traditional Chinese Medicine (TCM), where it’s known as “Da Huang.” Its medicinal uses date back thousands of years.

• Laxative and Purgative: This is perhaps its most ancient and well-documented use. Traditional practitioners utilized rhubarb to clear blockages, treat constipation, and “purge” the body of toxins.
• Anti-inflammatory and Antimicrobial: Historically, rhubarb root was also used topically for wounds and infections, and internally to address inflammatory conditions.
• Digestive Aid: Beyond its laxative effect, rhubarb was used to improve overall digestion and treat indigestion.

Side Effects of Rhubarb

While rhubarb offers impressive health benefits, it is important to be aware of its potential side effects, especially when consumed in large quantities or by certain individuals.

1. Oxalic Acid Content

Rhubarb stalks — and especially the leaves — contain oxalic acid, a naturally occurring compound that can bind to minerals like calcium and iron, reducing their absorption. High intake of oxalic acid may also contribute to kidney stone formation in susceptible individuals.

2. Highly Toxic Leaves

This cannot be overstated: rhubarb leaves are toxic and must never be consumed. They contain dangerously high levels of oxalic acid and anthraquinone glycosides that can cause nausea, vomiting, difficulty breathing, seizures, and in severe cases, kidney failure or death.

3. Laxative Effect

Due to compounds like sennosides, consuming large amounts of rhubarb can cause diarrhea, abdominal cramping, and loose stools. This effect is more pronounced with rhubarb root preparations than with the stalks.

4. Kidney Stone Risk

People with a history of kidney stones — particularly calcium oxalate stones — should be cautious with rhubarb consumption. The oxalates in rhubarb can contribute to stone formation when consumed in excess.

5. Medication Interactions

Rhubarb may interact with certain medications, including blood thinners (due to its Vitamin K content), diuretics, and heart medications. Always consult your doctor if you are on long-term medications.

6. Not Safe During Pregnancy or Breastfeeding

High-dose rhubarb preparations, particularly in supplement or herbal extract form, are not recommended during pregnancy or breastfeeding due to potential stimulant and laxative effects that could affect the developing baby.

7. May Worsen Kidney or Liver Disease

Individuals with pre-existing kidney or liver conditions should avoid excessive rhubarb consumption, as its oxalate and anthraquinone content may place additional strain on these organs.

How to Grow Rhubarb in Your Garden

Growing your own rhubarb is a rewarding experience, providing you with fresh, flavorful stalks for years to come. Rhubarb is a perennial plant, meaning it will come back year after year, and it’s surprisingly low-maintenance once established. Here’s a comprehensive guide to getting started.

1. Choosing a Location

Rhubarb thrives in full sun, meaning at least 6-8 hours of direct sunlight per day. It also prefers well-drained soil and needs plenty of space, as mature plants can spread up to 3-4 feet wide.

Choose a spot where it won’t be overshadowed by other plants or compete for nutrients. Since it’s a long-lived perennial, select a permanent home for it where it can remain undisturbed for many years.

2. Soil Preparation is Key

Rhubarb is a heavy feeder and appreciates rich, fertile soil.

• Soil Type: It prefers a slightly acidic to neutral pH (6.0 to 6.8). You can test your soil pH with a home testing kit.
• Amendments: Before planting, generously amend the soil with plenty of organic matter. This could be well-rotted compost, aged manure, or leaf mold. Dig it in deeply (at least 12-18 inches) to ensure good drainage and provide essential nutrients. Good drainage is crucial to prevent root rot.

3. Planting Rhubarb

You can plant rhubarb from crowns (root divisions) or from seed, though crowns are generally recommended for quicker establishment and true-to-type varieties.

From Crowns:

• When to Plant: The best time to plant rhubarb crowns is in early spring, as soon as the soil can be worked, or in the fall after the heat of summer has passed.
• How to Plant:
  1. Dig a hole that is large enough to comfortably accommodate the crown.
  2. Place the crown in the hole so that the top of the crown (where the buds are) is about 1-2 inches below the soil surface.
  3. Fan out the roots in the hole.
  4. Backfill with amended soil, gently firming it around the crown to remove air pockets.
  5. Water thoroughly immediately after planting.
• Spacing: Plant crowns 3-4 feet apart to allow for mature growth.

From Seed:

• Starting Seeds: Start rhubarb seeds indoors 6-8 weeks before the last frost date in your area. Sow seeds about ½ inch deep in seed-starting mix.
• Germination: Keep the soil consistently moist and warm (around 65-70°F or 18-21°C). Germination can be slow and erratic.
• Transplanting: Once seedlings are large enough to handle and all danger of frost has passed, transplant them outdoors, spacing them 3-4 feet apart. Keep in mind that rhubarb grown from seed may not be true to the parent plant and can take longer to establish.

4. Watering Rhubarb

Rhubarb needs consistent moisture, especially during dry spells and in its first year of growth.

• Establishment: Water deeply and regularly to help the plant establish a strong root system.
• Mature Plants: Once established, mature rhubarb plants are somewhat drought-tolerant but will produce larger, more succulent stalks with consistent moisture. Aim for about 1 inch of water per week, either from rain or irrigation.
• Mulching: Apply a thick layer of organic mulch (like straw, wood chips, or compost) around the base of the plants. This helps retain soil moisture, suppresses weeds, and keeps the soil cool.

5. Fertilizing Rhubarb

Given its heavy feeding nature, rhubarb benefits from regular fertilization.

• Spring Feeding: In early spring, as new growth emerges, top-dress the plants with a balanced organic fertilizer or a generous layer of well-rotted compost or aged manure.
• After Harvest: After the main harvest in late spring/early summer, you can apply another light feeding to help the plant recover and store energy for the next season.
• Avoid Nitrogen in Late Season: Avoid high-nitrogen fertilizers late in the season, as this can encourage leafy growth at the expense of root development for winter storage.

6. Pest and Disease Management

Rhubarb is generally a robust plant and not often plagued by serious pests or diseases.

• Pests: Slugs and snails might nibble on young leaves. Use organic slug baits or hand-pick them. Rhubarb curculio is a beetle that can bore holes in stalks; physical removal is the best method.
• Diseases: Crown rot can occur in poorly drained soil, leading to mushy crowns and yellowing leaves. Ensure good drainage. Leaf spot diseases can appear but are rarely serious; remove affected leaves if necessary.

7. Harvesting Rhubarb

This is where the patience pays off!

• First Year (Crucial!): DO NOT HARVEST ANY STALKS IN THE FIRST YEAR AFTER PLANTING. This allows the plant to put all its energy into developing a strong root system. Harvesting too early can weaken the plant and reduce future yields. You can remove any flower stalks that emerge to direct energy back into root growth.
• Second Year: You can begin to harvest lightly in the second year, taking only a few stalks from each plant.
• Third Year and Beyond: From the third year onwards, you can enjoy a full harvest.
• How to Harvest:
  1. Twist and Pull: Grasp the base of the stalk near the crown and twist firmly, pulling it away from the plant. Avoid cutting the stalks with a knife, as this can leave stubs that may rot.
  2. Leaves Off: Immediately remove and discard the toxic leaves.
  3. Quantity: Harvest about one-third to one-half of the mature stalks from a plant at any one time.
  4. Timing: The main harvest season is typically from mid-spring through early summer (April to June in many regions). Stop harvesting around mid-summer (July) to allow the plant to store energy for winter and the next season. Harvesting too late into the summer can weaken the plant.

8. Winter Care

Rhubarb is very cold-hardy.

• Dormancy: As temperatures drop in the fall, the leaves will yellow and die back. This is normal, as the plant enters dormancy.
• Cleanup: Cut back all remaining dead foliage to the ground after the first hard frost.
• Mulch: Apply a fresh layer of mulch (straw, compost, or leaves) over the crown to provide extra winter protection, especially in very cold climates.

9. Dividing Rhubarb

After about 5-10 years, rhubarb plants can become overcrowded, and their production may decline. This is a good time to divide them.

• When to Divide: Divide plants in early spring before new growth emerges, or in the fall after the leaves have died back.
• How to Divide:
• Carefully dig up the entire crown.
• Using a sharp spade or knife, divide the crown into several pieces, ensuring each piece has at least one strong bud and a good portion of roots.
• Replant the divisions as you would new crowns, spacing them appropriately. This revitalizes the plants and gives you new plants to expand your rhubarb patch or share with friends!

FAQs

1. Is rhubarb a fruit or a vegetable?

Botanically, rhubarb is a vegetable, as it is the stalk of a plant. However, it is legally classified as a fruit in the United States and is widely used in sweet, fruit-like culinary preparations.

2. Can you eat rhubarb raw?

Yes, raw rhubarb is edible, but it is extremely tart and astringent. Most people prefer it cooked with a sweetener to balance the flavor. Raw stalks can be dipped in sugar as a snack.

3. Are rhubarb leaves poisonous?

Yes, rhubarb leaves are toxic due to very high concentrations of oxalic acid and other harmful compounds. They should never be eaten and should be discarded safely away from children and pets.

4. What does rhubarb taste like?

Rhubarb has a very tart, sour, and slightly bitter flavor on its own. When cooked with sugar or paired with sweet fruits like strawberries, it develops a complex sweet-tart taste profile.

5. Can diabetics eat rhubarb?

Yes, rhubarb is low in sugar and calories, making it a suitable food for diabetics when consumed without large amounts of added sugar. Some research even suggests it may help with blood sugar regulation.

6. How do you freeze rhubarb?

Wash and chop rhubarb into pieces, spread on a tray to freeze individually, then transfer to airtight bags or containers. Frozen rhubarb keeps for up to 12 months.

7. Can rhubarb cause kidney stones?

In susceptible individuals, yes. Rhubarb is high in oxalic acid, which can combine with calcium to form calcium oxalate kidney stones. People with a history of kidney stones should limit their intake.

8. Does rhubarb have any drug interactions?

Yes. Rhubarb may interact with blood thinners (warfarin), diuretics, heart medications, and laxatives. Always consult your doctor if you are taking prescription medications.