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How to Plant, Grow, and Harvest Rhubarb


growing rhubarb

Rhubarb, scientifically known as Rheum rhabarbarum, is a perennial plant that is commonly used in culinary applications across diverse cultures. Its origin traces back to Asia, and over centuries, it has been adopted and cultivated worldwide, lending our dishes its distinctive tart flavor and vibrant red hue.


Rhubarb is unique because it's a vegetable that is often treated as a fruit in cooking. Its stalks are the only part of the plant that are edible and are often used in pies, compotes, and jams. The leaves of the rhubarb plant are not edible, as they contain high levels of oxalic acid, which can be toxic.


Beyond its culinary use, rhubarb also offers a range of health benefits. It's rich in vitamins C and K, along with dietary fiber and calcium. Additionally, rhubarb provides antioxidants and can aid digestion due to its dietary fiber content.


Growing rhubarb in your own garden can be a gratifying endeavor. Not only will you have a fresh supply of this unique vegetable (or fruit, in a culinary sense), but its large, lush leaves can add an exotic appeal to your garden.


In the upcoming sections, we'll delve into how you can plant, grow, and harvest rhubarb in your own garden, ensuring that you always have this versatile ingredient on hand when you're preparing a feast in the kitchen.



Optimal growing conditions for rhubarb - Climate, sunlight, and soil requirements Optimal


Rhubarb thrives best under specific conditions, including the right climate, adequate sunlight, and suitable soil. Here's what you need to know about each aspect to ensure your rhubarb plants flourish.


Climate

Rhubarb is a cold-hardy plant, preferring regions with cool, temperate climates. It can survive in USDA hardiness zones 3-8 and requires a chilling period with temperatures below 40°F to break dormancy and trigger spring growth.


Sunlight

While rhubarb can tolerate partial shade, it grows best in full sunlight. Aim to plant your rhubarb in a spot that receives at least six hours of direct sunlight per day.


Soil

Rhubarb prefers well-draining, fertile soil. Ideal soil pH is between 6.0 and 6.8, slightly acidic to neutral. Rhubarb is a heavy feeder, so incorporate plenty of organic matter, such as compost or well-rotted manure, into the soil before planting to provide a rich supply of nutrients.


Water

Rhubarb has a deep root system and prefers consistent moisture. However, it doesn't do well in waterlogged soil, which can lead to root rot. Ensure your soil drains well and provide consistent watering, especially during dry spells.


Understanding and meeting these growing conditions will set your rhubarb plants up for a successful growing season. As you'll find in the upcoming sections, this knowledge will play a key role in helping you plant, grow, and harvest bountiful crops of rhubarb in your garden.



Step-by-step Guide to Planting Rhubarb


growing rhubarb

When to Plant – Best time of the year for planting rhubarb


The ideal time to plant rhubarb depends on the method you're using – seeds, crowns, or transplants – and your local climate.


Planting Rhubarb from Seed

If you're starting rhubarb from seed, you'll want to begin indoors in late winter or early spring. This gives the plants a head start and allows them to establish before being transplanted outdoors.


Planting Rhubarb from Crowns or Transplants

Rhubarb is most commonly planted using crowns or transplants. These are typically planted in early spring as soon as the ground can be worked, but fall planting is also possible in areas with mild winters.


Climate Considerations

For regions with cold winters, early spring planting allows the rhubarb to establish before the intense heat of summer. In areas with milder winters and hot summers, consider planting in late fall, allowing plants to establish over the winter and early spring.


By choosing the optimal time to plant, you're giving your rhubarb the best start, leading to healthier plants and a more successful harvest.



Seed Selection – Choosing the right seeds for your garden


While it's more common to plant rhubarb from crowns or transplants, you can also grow it from seed. Selecting the right seeds is a crucial step in this process. Here are a few considerations to keep in mind.


Variety Selection

First, you'll need to decide on the variety of rhubarb you want to grow. There are several types to choose from, each with its own color, flavor profile, and growing characteristics. Some popular choices include 'Victoria', known for its sweet, mild flavor, and 'Canada Red', prized for its deep red stalks.


Seed Quality

When purchasing seeds, look for reputable seed companies that offer high-quality, disease-free seeds. You should also check the packing date on the seed packet. Fresh seeds, less than a year old, will have a higher germination rate.


Growing Conditions

Consider your local growing conditions when choosing your seeds. While rhubarb generally prefers cooler climates, some varieties may be more heat-tolerant than others.


Space Considerations

Rhubarb is a large plant that requires plenty of space to grow. Keep this in mind when deciding how many seeds to purchase and plant.


By selecting the right seeds for your garden, you'll be well on your way to growing a successful crop of rhubarb.



Site Preparation – How to prepare the garden bed or pot for planting


growing rhubarb

Proper site preparation is essential to growing healthy, productive rhubarb plants. Here's a step-by-step guide on how to prepare your garden bed or pot for rhubarb planting:


Choose a Suitable Location

Rhubarb needs a sunny location with well-drained soil. A spot that gets at least six hours of sun a day is ideal. Avoid low-lying areas where water may collect and cause root rot.


Prepare the Soil

Rhubarb prefers fertile, well-draining soil with a slightly acidic to neutral pH (6.0 to 6.8). Use a soil test kit to determine your soil's pH, and amend as needed with lime to raise the pH or sulfur to lower it.


Incorporate a generous amount of compost or well-rotted manure into the soil to improve fertility and drainage. If you're planting in a pot, use a high-quality potting mix with added compost.


Create Planting Holes or Beds

Rhubarb plants need plenty of space to grow. If planting in a garden bed, create a trench about 4 inches deep and space planting holes 3 to 4 feet apart. In a pot, choose one that is at least 12-15 inches deep and equally as wide.


Plan for Crop Rotation

Rhubarb is a perennial plant that can produce for up to 10-15 years, so it's not typically rotated like annual crops. However, you should avoid planting rhubarb in a bed or pot where previous crops had diseases that could affect it.



Planting Process - Detailed Steps on How to Plant Seeds or Seedlings


Planting rhubarb correctly is key to a successful harvest. Whether you're using seeds, crowns, or transplants, we've outlined a clear process for you below.


Planting from Seed


1. Start Indoors: Start rhubarb seeds indoors about 8 weeks before the last expected spring frost.


2. Sow Seeds: Plant seeds 1/4 inch deep in seed-starting mix. Keep the soil consistently moist but not waterlogged.


3. Transplant Seedlings: Once the seedlings have developed two true leaves and the risk of frost has passed, harden them off and transplant them into the garden.


Planting Crowns or Transplants


1. Prepare the Crown: If planting a crown, be sure it is fresh and healthy. It should have at least one strong bud.


2. Dig a Hole: In your prepared garden bed, dig a hole large enough to comfortably accommodate the root system of the crown or transplant.


3. Plant the Crown or Transplant: Place the crown or transplant in the hole with the bud(s) pointing upwards and the roots spread out and downward. The top of the crown should be just below the soil surface. For transplants, the soil level should match the one they were grown in.


4. Backfill the Hole: Fill in the hole with soil, pressing it gently around the roots. Water thoroughly.


Final Tips

  • Rhubarb is a large plant, so be sure to allow 3 to 4 feet of space between plants.

  • If planting more than one row, allow at least 5 feet between rows.

  • Keep the planting area weed-free and water regularly, but do not let the soil become waterlogged.

Following these steps will provide your rhubarb plants with a solid foundation to grow and thrive.



Care for Growing Rhubarb


growing rhubarb

Watering – How often and how much to water the plants


Proper watering is vital to the growth and productivity of your rhubarb plants. Here's a guide on how to water them efficiently:


Frequency

Rhubarb plants are fairly hardy and can withstand periods of dry weather. However, during the growing season, it's essential to maintain consistently moist soil, especially during dry spells. In most climates, this equates to watering once a week. However, in hotter or drier climates, watering may need to be increased to two or three times a week.


Quantity

When watering, aim to soak the soil to a depth of at least six inches. This encourages the plants to develop deep root systems, enhancing their drought resistance. On average, this means applying about one inch of water per week, but this could vary depending on your soil type. Sandy soils will need watering more frequently, while clay soils retain water longer and require less frequent watering.


Timing

The best time to water rhubarb is in the early morning, which reduces evaporation and allows the foliage to dry out during the day, reducing the risk of fungal diseases.


Other Considerations

Avoid overwatering, as waterlogged soil can lead to root rot. If you're unsure, check the soil by inserting a finger to a depth of about two inches. If the soil feels dry at this depth, it's time to water.


Mulching around your plants can help conserve moisture in the soil, reducing the frequency of watering required. It also helps to control weeds and adds nutrients to the soil as it breaks down.



Fertilizing – The type of fertilizer needed and how to apply it


Just like any other plant, rhubarb benefits from regular fertilization to support its growth and productivity. Here's a guide to help you understand what type of fertilizer is needed and how to apply it properly.


Choosing the Right Fertilizer

Rhubarb thrives on a balanced diet, and a fertilizer with a balance of nitrogen, phosphorus, and potassium, such as a 10-10-10, is typically a good choice. Rhubarb also appreciates high levels of organic matter, so adding compost or well-rotted manure can be beneficial.


When to Fertilize

The best time to apply fertilizer to your rhubarb plants is in the early spring when the new growth begins to emerge. This will provide the plants with the nutrients they need for the upcoming growing season.


How to Apply


1. Measure the Fertilizer: Follow the instructions on the fertilizer package to determine the correct amount for your garden size.


2. Prepare the Soil: Before applying the fertilizer, water the soil around your rhubarb plants to ensure it is moist but not waterlogged.


3. Apply the Fertilizer: Sprinkle the fertilizer around the base of each plant, ensuring it's evenly distributed. Take care not to let the fertilizer come into contact with the stems or leaves as it can cause burns.


4. Water Again: After applying the fertilizer, water the area again. This helps to move the nutrients into the root zone where they can be absorbed by the plant.


Fertilizing your rhubarb plants in this way will give them the nutrients they need to produce healthy stalks and leaves.



Disease and Pest Control – Common diseases and pests that can affect rhubarb, and how to manage them


While rhubarb is typically a hardy plant, it is not immune to diseases and pests. Here are some of the most common threats and how to deal with them effectively.


Diseases


1. Crown Rot: Crown rot is a fungal disease that can cause rhubarb plants to wilt and die. Prevent it by ensuring your plants have good drainage and air circulation, and avoid overwatering. Infected plants should be removed and destroyed to prevent the disease from spreading.


2. Leaf Spot: Leaf spot causes small, brown, and circular spots on rhubarb leaves. This disease is usually not serious, but severe infections can reduce plant vigor. To manage leaf spot, keep the foliage dry and ensure plants have enough space for air to circulate.


Pests


1. Rhubarb Curculio: Rhubarb curculio is a type of weevil that can burrow into rhubarb stalks, causing them to wilt. Handpicking is the most effective control method. If infestations are severe, consider using a suitable insecticide.


2. Slugs and Snails: These pests can chew holes in the rhubarb leaves. Slugs and snails can be manually removed or controlled with diatomaceous earth or slug bait.


General Pest and Disease Management

Practicing good garden hygiene can prevent many pest and disease problems. Remove and dispose of plant debris promptly, especially if it's diseased, as it can harbor pests and disease pathogens. Rotate crops, if possible, to break the life cycle of pests and diseases.


Healthy plants are more resistant to pests and diseases, so keep your rhubarb plants well-watered and adequately fertilized. Being alert to the first signs of disease or pests and dealing with them swiftly can save your crop.



Harvesting Rhubarb


growing rhubarb

When to Harvest – Identifying signs that the rhubarb is ready for harvesting


Rhubarb is a plant that rewards patience, and knowing when to harvest is essential for its long-term productivity and the quality of the crop. Here are key signs to look for and guidelines to ensure that you're harvesting your rhubarb at the right time.


Signs of Maturity

Rhubarb is typically ready for harvest in the second or third year after planting, depending on how healthy and fast-growing the plant is. Harvesting too early can weaken the plant, as it needs time to establish a robust root system.


Appropriate Harvest Time

Rhubarb's main harvest season falls in spring and early summer. Although it continues growing throughout the summer, it's advisable not to harvest past late June, as the stalks can become woody and less flavorful. In the first year of planting, resist the temptation to harvest. In the second year, you can begin to pick a few stalks, leaving plenty to continue feeding the plant.


Visual Indicators

Look for stalks that are at least 10-15 inches long and fully colored, typically a deep red or green, depending on the variety. The leaves should be large and fully opened. Remember, rhubarb stalks are harvested by color and size, not by the age of the plant.


Considerations

Even though the stalks are edible, the leaves of rhubarb are toxic if ingested due to high levels of oxalic acid. Always remove and discard the leaves immediately after harvesting the stalks.



How to Harvest – Techniques for harvesting rhubarb to prevent damage to the plant and fruit


Harvesting rhubarb correctly is crucial for the health of the plant and to ensure a continuous yield throughout the season. The process is straightforward, but it requires a bit of care. Here's how you can harvest rhubarb while keeping the plant robust and healthy.


Step-by-Step Harvesting Process


1. Identify Ready Stalks: Look for stalks that have reached the appropriate size and color. Stalks should be at least 10-15 inches long and show a vibrant color, either deep red or green depending on the variety.


2. Hold the Stalk Firmly: Grasp the chosen stalk down at the base, near where it emerges from the ground. Hold it firmly but avoid squeezing it too hard.


3. Pull and Twist: Pull upwards on the stalk while giving it a slight twist. The stalk should come away from the plant relatively easily. Never cut the stalk, as the remaining stub can rot and potentially damage the crown.


4. Remove the Leaf: Immediately after you've harvested the stalk, cut off the leaf at the top and dispose of it. Remember, rhubarb leaves are toxic and should not be consumed.


Harvesting Tips

  • Don't harvest all the stalks from a single plant at one go. Always leave at least two stalks per plant to ensure it continues to grow and produce.

  • It's essential to give the plant a rest period after a heavy harvest. This helps the rhubarb plant recover and generate new stalks for future harvests.

  • If a flowering stalk emerges, cut it off at the base as soon as possible. Flowering can weaken the plant and reduce the quality of the stalks.


Post-Harvest Care and Storage – How to store and preserve rhubarb for maximum freshness and longevity


Once you have harvested your rhubarb, proper post-harvest care and storage is crucial to maintain its freshness and longevity. Here are some tips on how to store and preserve your freshly picked rhubarb stalks.


Cleaning and Preparing


1. Wash Thoroughly: Rinse the harvested rhubarb stalks under cool water to remove any dirt or debris.


2. Dry Completely: Pat the stalks dry using a clean towel to remove any excess moisture. Water can promote mold growth during storage, so ensure the stalks are fully dry before storing.


3. Trim Ends: Trim both ends of the rhubarb stalks. The base can be particularly tough, so remove it entirely.


Storage Options

  • Refrigerate: Rhubarb can be stored in the refrigerator for up to two weeks. Place the stalks in a sealed plastic bag to retain moisture and keep them in the vegetable crisper drawer of your fridge.

  • Freeze: If you plan to store rhubarb for longer, freezing is a good option. Cut the stalks into 1-inch pieces, spread them out on a baking sheet, and freeze. Once frozen, transfer the rhubarb pieces into freezer bags or containers. Rhubarb can maintain its quality for up to a year when properly frozen.

  • Preserve: Rhubarb can also be canned or made into preserves or jams. This not only extends its shelf life but also provides a tasty way to enjoy rhubarb throughout the year.

Remember, only the stalks of the rhubarb plant are edible. The leaves contain high levels of oxalic acid and can be harmful if ingested. Always discard the leaves immediately after harvesting.



Frequently Asked Questions (FAQ)


How long does it take for rhubarb to grow?

Rhubarb typically takes about one year to establish itself properly. You should only start to harvest stalks in the second year, and by the third year, the plant will be ready for full harvesting.



Recap and Final Thoughts: Time to Start Planting, Growing, and Harvesting Rhubarb


In this comprehensive guide, we've covered a range of topics that will help you embark on your journey of planting, growing, and harvesting rhubarb. Here's a quick recap of the essential points:


1. Optimal Growing Conditions: Rhubarb thrives in climates with a distinct winter chill and enjoys full sun to partial shade. It prefers well-drained, compost-rich soil with a pH between 6.0 and 6.8.


2. When to Plant: Plant rhubarb during the early spring as soon as the ground is workable.


3. Seed Selection: It's best to use rhubarb crowns or divisions for planting, as rhubarb from seed is not typically true to type.


4. Site Preparation: Choose a sunny, well-draining spot and prepare the ground by adding plenty of organic matter.


5. Planting Process: Plant rhubarb crowns 2-3 feet apart with the bud facing upwards, and cover with about 2 inches of soil.


6. Watering and Fertilizing: Regular watering is essential, and a high-nitrogen fertilizer should be applied annually.


7. Disease and Pest Control: Regular monitoring and organic control measures can help manage common pests and diseases that affect rhubarb.


8. When and How to Harvest: Begin light harvesting in the second year, and full harvesting from the third year onwards, usually in the spring.


9. Post-Harvest Care and Storage: Store rhubarb stalks in the refrigerator, freeze for long-term storage, or preserve as jams or preserves.


Now, with all this knowledge at your disposal, it's time to roll up your sleeves and get started! Rhubarb is a rewarding plant to grow, not only for its unique flavor and culinary uses but also for the striking appearance it lends to your garden.


Plus, once established, rhubarb will provide you with a bountiful harvest year after year. Remember, the joy of gardening lies as much in the process as in the harvest. So, embrace the journey and happy gardening!