How to Grow Red Rhubarb: A Comprehensive Guide to Vibrant Stalks

Rhubarb, with its tart and tangy flavor, is a perennial garden favorite, adding a unique zing to pies, jams, and sauces. But beyond its culinary uses, rhubarb boasts beautiful, robust stalks. While green stalks are perfectly edible, it’s the vibrant red rhubarb that captures the eye and often fetches a higher price at farmers’ markets. So, how do you encourage your rhubarb to develop that desirable crimson hue? This guide will delve into the secrets of achieving the reddest rhubarb stalks possible, covering everything from variety selection to cultivation techniques.

Choosing the Right Rhubarb Variety for Red Stalks

The foundation of red rhubarb lies in selecting the right variety. Not all rhubarb is created equal when it comes to color. Some varieties are genetically predisposed to produce much redder stalks than others. Before you even think about planting, research and choose a variety known for its intense red coloring.

Popular Red Rhubarb Varieties

Several rhubarb varieties are celebrated for their vibrant red stalks. Some of the most popular include:

• ‘Canada Red’: As the name suggests, ‘Canada Red’ is known for its incredibly intense red stalks. The flavor is also excellent, offering a balance of tartness and sweetness. This variety is a reliable choice for consistent red coloring.

• ‘Crimson Red’: This variety is another popular choice, producing bright red stalks with a good flavor profile. It’s a reliable producer and a good option for home gardeners.

• ‘Valentine’: ‘Valentine’ is a classic variety known for its deep red stalks and vigorous growth. It’s a dependable choice and widely available.

• ‘Cherry Red’: True to its name, ‘Cherry Red’ produces stalks that are a rich cherry-red color. The flavor is tart and refreshing, making it ideal for pies and jams.

• ‘Livingston’: This is an older variety and more difficult to find, but one of the reddest varieties available. If you can find it, it’s well worth growing.

Choosing the right variety is paramount for success. Even with perfect growing conditions, a green-stalked variety will never produce the deep red hue you desire.

Optimizing Growing Conditions for Red Rhubarb

Once you’ve selected the right variety, providing optimal growing conditions is crucial for maximizing red color development. Rhubarb, like any plant, thrives when its needs are met. Soil, sunlight, and proper care all play vital roles in the intensity of its stalk color.

Soil Preparation and Nutrition

Rhubarb prefers well-drained soil that is rich in organic matter. Before planting, amend your soil with plenty of compost or well-rotted manure. This will improve drainage, provide essential nutrients, and create a healthy environment for your rhubarb to thrive.

• Soil pH: Rhubarb prefers a slightly acidic to neutral soil pH, ideally between 6.0 and 6.8. You can test your soil pH with a home testing kit or by sending a sample to your local agricultural extension office. If your soil is too alkaline, you can amend it with sulfur or peat moss.

• Fertilizing: Rhubarb is a heavy feeder and benefits from regular fertilization. Apply a balanced fertilizer in early spring, just as the plant begins to grow. Avoid over-fertilizing with nitrogen, as this can promote excessive leaf growth at the expense of stalk color. A fertilizer with a higher phosphorus and potassium content will encourage strong root development and vibrant stalk color.

• Mulching: Mulching around your rhubarb plant with organic materials like straw, wood chips, or compost helps to retain moisture, suppress weeds, and regulate soil temperature. Mulch also gradually releases nutrients into the soil, providing a slow-release fertilizer.

Rich, well-drained soil is the key to healthy rhubarb and vibrant red stalks.

Sunlight Requirements

Rhubarb needs plenty of sunlight to thrive and develop its characteristic red color. Aim for at least six hours of direct sunlight per day. In hotter climates, some afternoon shade may be beneficial to prevent the leaves from scorching.

• Location: Choose a planting location that receives full sun and is sheltered from strong winds. Windy conditions can damage the large leaves of the rhubarb plant.

• Spacing: When planting multiple rhubarb plants, space them at least three to four feet apart to allow for adequate air circulation and sunlight penetration.

Adequate sunlight is essential for the development of vibrant red color in rhubarb stalks.

Watering and Moisture Management

Rhubarb needs consistent moisture, especially during dry periods. Water deeply and regularly, ensuring that the soil remains moist but not waterlogged. Avoid overhead watering, as this can promote fungal diseases.

• Watering Frequency: The frequency of watering will depend on your local climate and soil type. Check the soil moisture regularly and water when the top inch feels dry.

• Drainage: Proper drainage is crucial for preventing root rot. If your soil is heavy clay, amend it with organic matter to improve drainage.

Consistent moisture is important, but avoid overwatering to prevent root rot.

Cultivation Techniques to Enhance Red Color

Beyond variety selection and optimal growing conditions, certain cultivation techniques can further enhance the red color of your rhubarb stalks. These techniques focus on manipulating the plant’s environment and growth patterns to favor the development of vibrant red pigment.

Forcing Rhubarb for Early and Redder Stalks

Forcing rhubarb involves covering the plant with a dark container, such as a forcing jar or a large bucket, to exclude light. This process tricks the plant into thinking it’s spring, causing it to produce early stalks that are often more tender and intensely colored.

• How to Force Rhubarb: In late winter or early spring, once the plant has been exposed to several weeks of cold temperatures, cover it with a forcing jar or bucket. Make sure the container is opaque to completely block out light.

• Benefits of Forcing: Forcing rhubarb results in earlier harvests, more tender stalks, and often a more intense red color. The stalks grown in the dark are typically sweeter and less acidic.

• Important Considerations: Only force rhubarb plants that are at least three years old. Forcing weakens the plant, so only force it every other year to allow it to recover. After forcing, remove the container and allow the plant to grow normally for the rest of the season.

Forcing rhubarb is a proven technique for producing earlier, redder, and more tender stalks.

Harvesting Rhubarb Properly

The way you harvest rhubarb can also influence the color of subsequent stalks. Harvesting the stalks properly ensures the plant’s continued health and promotes the development of vibrant red color in future growth.

• When to Harvest: Harvest rhubarb stalks when they are at least 12 inches long and about an inch thick. Avoid harvesting during the first year after planting to allow the plant to establish itself.

• How to Harvest: To harvest rhubarb, grasp the stalk near the base and gently pull it away from the plant with a twisting motion. Avoid cutting the stalks, as this can leave behind a stub that can rot and attract pests.

• Harvesting Frequency: Harvest rhubarb stalks selectively, removing only a few stalks from each plant at a time. Avoid harvesting more than one-third of the plant’s stalks in a single harvest to ensure its continued health.

• Stopping Harvesting: Stop harvesting rhubarb in mid-summer to allow the plant to build up its energy reserves for the following year.

Proper harvesting techniques promote plant health and contribute to the development of vibrant red stalks in subsequent harvests.

Addressing Potential Problems

Even with the best care, rhubarb can sometimes encounter problems that can affect its health and color. Addressing these issues promptly is essential for maintaining a healthy and productive plant.

• Pests and Diseases: Rhubarb is generally resistant to pests and diseases, but it can sometimes be affected by crown rot or rhubarb curculio. Crown rot is a fungal disease that can cause the plant to rot at the base. Rhubarb curculio is a weevil that can damage the stalks and leaves.

• Nutrient Deficiencies: Nutrient deficiencies can also affect the color and health of rhubarb stalks. Yellowing leaves or stunted growth can indicate a nutrient deficiency. Amend the soil with compost or fertilizer to address any deficiencies.

Addressing potential problems promptly is essential for maintaining healthy rhubarb plants and vibrant red stalks.

Troubleshooting Common Rhubarb Color Issues

Sometimes, despite your best efforts, your rhubarb stalks might not be as red as you’d hoped. Here’s how to troubleshoot common color-related issues:

Green Stalks Despite a Red Variety

Even if you’ve chosen a red variety, environmental factors can still influence the intensity of the color.

• Insufficient Sunlight: Ensure your rhubarb plant is receiving at least six hours of direct sunlight per day.

• Over-Fertilization with Nitrogen: Too much nitrogen can promote leaf growth at the expense of stalk color. Use a balanced fertilizer or one with a higher phosphorus and potassium content.

• Soil Conditions: Make sure your soil is well-drained and rich in organic matter. Amend the soil with compost or well-rotted manure.

Fading Color After Harvesting

Sometimes, rhubarb stalks can lose some of their color after they’ve been harvested.

• Storage: Store harvested rhubarb stalks in a cool, dark place to prevent color fading.

• Processing: Process or freeze rhubarb as soon as possible after harvesting to preserve its color and flavor.

Understanding the potential causes of color-related issues is crucial for troubleshooting and achieving the desired vibrant red stalks.

By carefully selecting the right variety, optimizing growing conditions, and employing effective cultivation techniques, you can significantly increase your chances of growing rhubarb with beautiful, vibrant red stalks. Remember that patience is key, and with consistent care, you’ll be rewarded with a bountiful harvest of delicious and colorful rhubarb.

What is the best time of year to plant red rhubarb?

The ideal time to plant red rhubarb is either in early spring or late fall. Planting during these cooler periods allows the rhubarb crown to establish its root system before the stresses of summer heat or winter cold fully set in. The soil is usually more workable and moisture is more readily available, aiding in root development and overall plant health.

Avoid planting during the peak of summer or the depths of winter. Summer heat can scorch the young plant, while frozen ground in winter makes planting virtually impossible and could damage the dormant crown. Aim for a period when the soil is cool and moist, but not waterlogged or frozen, for optimal establishment.

What kind of soil does red rhubarb need?

Red rhubarb thrives in well-drained soil that is rich in organic matter. Amending the soil with compost, well-rotted manure, or other organic materials before planting is crucial for providing the necessary nutrients and improving drainage. Rhubarb prefers a slightly acidic to neutral soil pH, ideally between 6.0 and 6.8.

Heavy clay soils should be amended with plenty of organic matter to improve drainage and aeration. Sandy soils benefit from organic matter additions to help retain moisture and nutrients. Proper soil preparation is essential for healthy rhubarb growth and vibrant red stalks.

How much sunlight does red rhubarb require?

Red rhubarb needs at least six hours of direct sunlight per day to thrive and produce vibrant red stalks. While it can tolerate some partial shade, especially in hotter climates, insufficient sunlight will result in weaker plants and less colorful stalks. A sunny location is crucial for maximizing growth and color development.

Ensure the chosen planting location receives ample sunlight throughout the growing season. Observing the area throughout the day can help determine if it receives enough direct sunlight. If partial shade is unavoidable, try to ensure the plant receives morning sun, which is less intense than afternoon sun.

How often should I water my red rhubarb plant?

Water rhubarb deeply and regularly, especially during dry periods. Aim for consistent soil moisture, but avoid overwatering, which can lead to root rot. Young plants require more frequent watering as their root systems develop, while established plants are more drought-tolerant.

Check the soil moisture regularly by sticking your finger a few inches into the soil. If the soil feels dry to the touch, it’s time to water. Avoid letting the soil dry out completely, especially during hot weather. Mulching around the plant can help retain soil moisture and reduce the need for frequent watering.

When can I harvest red rhubarb stalks?

Do not harvest any stalks during the first year after planting, allowing the plant to establish itself. In the second year, harvest only a few stalks. From the third year onward, you can harvest more liberally, but avoid taking more than one-third of the plant at any one time.

Harvest rhubarb stalks in spring or early summer, typically from April to June. Stalks are ready to harvest when they are at least 10-15 inches long and have a good red color. Grasp the stalk near the base and gently pull and twist until it comes free from the crown. Avoid cutting the stalks, as this can leave behind a stub that can rot and damage the crown.

How do I fertilize my red rhubarb plant?

Fertilize red rhubarb in early spring, just as new growth begins to emerge. Use a balanced fertilizer, such as a 10-10-10, or an organic fertilizer like composted manure or bone meal. Avoid over-fertilizing, as this can lead to excessive leaf growth at the expense of stalk production.

Apply the fertilizer according to the package instructions, spreading it evenly around the base of the plant. Water the fertilizer into the soil to help it reach the roots. Consider a second, lighter feeding after the main harvest period to support continued growth and vigor.

How do I overwinter my red rhubarb plant?

In colder climates, protect red rhubarb plants during the winter by applying a thick layer of mulch around the crown. This helps insulate the roots and prevent them from freezing. Straw, hay, or shredded leaves are all good options for mulch.

Remove the mulch in early spring as new growth begins to emerge. This allows the soil to warm up and promotes faster growth. In milder climates, mulching may not be necessary, but it can still help protect the plant from extreme temperature fluctuations.