How To Grow Rhubarb

Dreaming of homegrown rhubarb for those delicious pies and crumbles? You’re in the right place! Growing this vibrant perennial is easier than you think, and we’re here to show you exactly how to do it. Let’s dig in and get your rhubarb patch thriving so you can enjoy a bountiful harvest for years to come.

How to Grow Rhubarb from Planting to Harvest

Choosing the Best Rhubarb Varieties for Your Garden

Selecting the right rhubarb variety is the first step toward a bountiful harvest. For most gardeners, Victoria is a top pick because it offers reliable yields and a sweet, tart flavor that works perfectly in pies and jams.

If you live in a colder climate, consider Canada Red, which is extremely hardy and produces deep red stalks that look stunning in any garden. For those in warmer regions, look for varieties like Macdonald that can handle a bit more heat without wilting.

Always choose disease-free crowns from a reputable nursery to ensure your plants get off to a strong start. Remember, rhubarb is a perennial, so you’ll be enjoying these plants for years to come, making it worth the effort to pick a variety that suits your taste and growing conditions.

When to Plant Rhubarb Crowns or Seeds

Timing is everything when planting rhubarb, and crowns are your best bet for success. The ideal time to plant dormant crowns is in early spring, as soon as the ground can be worked, or in late fall when the plant is going dormant.

This gives the roots time to establish before the heat of summer or the freeze of winter. While you can grow rhubarb from seeds, it takes much longer to produce a harvest, often up to two years, and the plants may not inherit the desired traits of the parent plant.

If you do choose seeds, start them indoors in late winter and transplant seedlings outside after the last frost. For quicker results, stick with crowns or divisions, which can often be harvested lightly in their second year.

Preparing the Soil for Optimal Growth

Rhubarb thrives in fertile, well-draining soil that is rich in organic matter, so proper preparation is key. Start by choosing a sunny spot, though rhubarb will tolerate some light afternoon shade in hotter climates.

Loosen the soil to a depth of at least 12 inches and mix in plenty of compost or well-rotted manure to provide essential nutrients. Rhubarb is a heavy feeder, so ensuring the soil is nutrient-dense at planting time will support vigorous growth for seasons to come.

Aim for a soil pH between 6.0 and 6.8 for the best results. Before planting, remove any rocks or weeds that could compete with your young plants.

Once established, apply a thick layer of organic mulch around the base to retain moisture and suppress weeds, but keep it away from the crown to prevent rot.

Step-by-Step Guide to Planting Rhubarb

How to Space and Position Rhubarb Crowns

When planting rhubarb, start by selecting a sunny spot with at least six hours of sunlight daily, though some afternoon shade is beneficial in hotter climates. Proper spacing is crucial because these plants can grow quite large and live for years, so you don’t want them overcrowded.

Space each crown about 3 to 4 feet apart in rows that are at least 4 feet wide. This generous spacing ensures good air circulation, which helps prevent fungal diseases, and gives the massive leaves plenty of room to spread.

If you’re planting multiple rows, keep them about 4 to 5 feet apart to make harvesting easier later on. Remember, rhubarb is a long-term investment in your garden, so taking the time to position them correctly right now will save you a lot of headaches down the road.

Proper Depth and Mulching Techniques

Dig a generous hole for each crown, ensuring it is wide enough to accommodate the roots without bending them. Place the crown so the top sits just 1 to 2 inches below the soil surface.

Planting too deep can rot the crown, while planting too shallow exposes it to harsh weather. Once planted, backfill the hole gently with soil and water thoroughly to settle the earth around the roots.

After planting, apply a 2 to 3-inch layer of organic mulch, such as straw, shredded leaves, or compost, around the base of the plant. This mulch helps retain moisture, suppresses weeds, and regulates soil temperature during extreme weather.

Just be careful to keep the mulch a few inches away from the crown itself to prevent rot.

Watering Newly Planted Rhubarb

Water is absolutely essential immediately after planting to help settle the soil and eliminate air pockets around the roots. Give your new rhubarb a deep, thorough soaking right away. For the first few weeks, keep the soil consistently moist but not waterlogged, checking the top inch of soil regularly.

If it feels dry, it is time to water again. Established rhubarb is somewhat drought-tolerant, but young plants need steady moisture to develop strong root systems. As the plant matures, you can reduce watering frequency, aiming for about 1 inch of water weekly during dry spells.

Always water at the base of the plant early in the morning to allow the leaves to dry out during the day, reducing the risk of disease.

Essential Care and Maintenance for Healthy Rhubarb

Watering Requirements Throughout the Season

Rhubarb thrives with consistent moisture, especially during its peak growing season in spring and early summer. Aim to provide about 1-2 inches of water per week, either through rainfall or manual watering. If the weather turns hot and dry, increase watering to keep the soil evenly moist but not waterlogged.

A good rule of thumb is to check the top inch of soil—if it feels dry, it’s time to water. Deep, infrequent watering encourages strong root development, while shallow watering can lead to weak plants.

Adding a layer of mulch around the base helps retain moisture and reduces the need for frequent watering. Remember, rhubarb is a heavy drinker, so keeping up with its hydration needs ensures tender, flavorful stalks for harvest.

Fertilizing Schedule for Maximum Yield

To keep your rhubarb productive, feed it annually in early spring before new growth begins. A balanced, all-purpose fertilizer or a layer of well-rotted compost works wonders. Apply about ½ cup of fertilizer per plant, spreading it evenly around the base but avoiding direct contact with the crown.

If you notice sluggish growth or pale leaves, a mid-season boost with a nitrogen-rich fertilizer can help. Avoid over-fertilizing, as too much nitrogen can promote leafy growth at the expense of stalks.

For established plants, a side dressing of compost or aged manure in late fall can also provide nutrients for the next season. Consistent feeding ensures your rhubarb stays vigorous and produces bountiful harvests year after year.

Weed Control and Mulching Strategies

Weeds compete with rhubarb for nutrients and water, so keeping them in check is crucial. Hand-pull weeds regularly, especially close to the crown, to avoid disturbing the shallow roots.

Applying a 2-3 inch layer of organic mulch, such as straw, shredded leaves, or wood chips, is an effective way to suppress weeds while retaining soil moisture. Mulch also keeps the soil cool during hot spells, which rhubarb appreciates.

Just be sure to keep mulch a few inches away from the crown to prevent rot. If weeds become stubborn, a light hoeing can help, but be gentle to avoid damaging the roots.

A clean, mulched bed not only reduces maintenance but also creates a healthier environment for your rhubarb to thrive.

How to Divide and Transplant Rhubarb Plants

Signs Your Rhubarb Needs Dividing

If your rhubarb plant looks like it’s trying to escape its pot or garden bed, it’s probably time to divide it. One clear sign is thin, spindly stalks that don’t have the usual robust flavor or thickness.

Overcrowded roots struggle to produce quality stems, so you might notice fewer harvests or smaller leaves. Another clue is when the center of the plant starts to die back or looks sparse, despite the outer edges thriving. This usually happens every 3-5 years as the plant grows.

Dividing not only revives the original plant but also gives you new ones to share or expand your garden. Keep an eye out for these signs to ensure your rhubarb stays healthy and productive for years to come.

Best Time of Year to Divide Crowns

Timing is everything when it comes to dividing rhubarb. The ideal time is early spring, just as new growth begins to emerge, or in late fall after the plant goes dormant. Avoid dividing during summer heat, as the stress can weaken the plant.

In spring, wait until you see small red buds pushing through the soil—this means the plant is waking up and ready to handle disturbance. If you choose fall, wait until the foliage has died back after the first frost. This gives the roots time to settle before winter.

Dividing at the right time ensures the crowns establish quickly and grow vigorously. Remember, rhubarb is a hardy perennial, but giving it the best start will pay off with bountiful harvests.

Techniques for Digging Up and Replanting

Start by digging around the entire plant with a spade, keeping about 6 inches of space from the crown to avoid damaging roots. Lift the clump carefully and shake off excess soil to see the root structure.

Use a sharp knife or garden fork to divide the crown into smaller sections, each with at least 2-3 buds and healthy roots. Discard any old or rotten pieces. Replant the divisions in well-draining soil rich with organic matter, positioning the buds just below the surface.

Space them 3-4 feet apart to allow room to grow. Water thoroughly after planting to settle the soil. Mulch around the base to retain moisture and suppress weeds. With proper care, your new divisions will thrive and produce delicious stalks in no time.

Common Pests and Diseases Affecting Rhubarb

Identifying and Treating Rhubarb Crown Rot

Rhubarb crown rot is a frustrating issue that can turn your thriving patch into a mushy mess. You’ll usually notice stunted growth or rotting bases near the soil, often with a foul smell. To tackle this, start by digging up the infected plant and carefully inspect the roots.

If the crown is soft and dark brown, it’s likely rot. Cut away the affected parts, leaving only healthy, firm tissue. Let the healthy sections dry for a few hours before replanting in fresh, well-draining soil.

Prevention is key, so avoid planting in waterlogged areas and space your plants for good airflow. Mulching lightly can help retain moisture without suffocating the roots. If the plant is too far gone, remove it entirely to stop the spread to nearby plants.

A little proactive care ensures your rhubarb stays healthy and productive for years.

Managing Pests Like Rhubarb Curculio

The rhubarb curculio, a snout-nosed beetle, can bore into stalks and crowns, causing damage. These pests leave small holes or notches in the stems, weakening the plant over time. To manage them, handpick any visible beetles and drop them in soapy water.

Keep the area free of weeds, as they often hide in nearby debris. Neem oil or insecticidal soap can also help if applied early in the season. If you notice severe damage, remove and destroy infested stalks to prevent larvae from spreading.

Regularly inspect your plants, especially in spring when curculios are most active. Maintaining a clean garden and encouraging beneficial insects like ladybugs can naturally reduce pest populations. With consistent monitoring, you can keep these pesky bugs at bay and enjoy a bountiful rhubarb harvest.

Preventing Leaf Spot and Fungal Issues

Leaf spot and fungal issues show up as yellow or brown spots on rhubarb leaves, which can reduce vigor. To prevent this, water at the base of the plant rather than overhead to keep foliage dry. Avoid overcrowding by spacing plants properly, ensuring good air circulation.

Remove any infected leaves promptly and dispose of them in the trash—don’t compost them! Applying a layer of mulch can also help by splashing soil-borne fungi onto leaves. If fungal problems persist, a copper-based fungicide can be used as a last resort.

Rotate your crops every few years and maintain clean garden practices to minimize recurrence. Healthy, well-fed plants are more resistant to diseases, so enrich your soil with compost. These simple steps will keep your rhubarb looking lush and disease-free.

When and How to Harvest Rhubarb Safely

Knowing the Right Time to Pick Stalks

Knowing when your rhubarb is ready is key to a sweet, successful harvest. Wait until the stalks are at least 10-15 inches long, which usually happens in late spring or early summer, depending on your climate.

Thick, firm stalks indicate the plant has enough energy stored, so avoid picking thin or spindly ones. Gently tug on the stalks; if they resist, give them a few more days. The color isn’t a perfect indicator—both red and green varieties can be tasty—but deeper shades often mean sweeter flavor.

Harvest during the cooler parts of the day, like early morning, to keep the stalks crisp. For the first year after planting, resist the urge to harvest; let the plant establish strong roots.

By the second or third year, you can enjoy a bountiful crop for 4-6 weeks, then stop to let the plant recharge for next season.

Correct Harvesting Techniques to Avoid Plant Damage

Harvesting rhubarb the right way keeps your plant healthy for years to come. Always pull stalks instead of cutting them—use a steady, gentle twist at the base where the stalk meets the crown. This method naturally separates the stalk without leaving a stub that could rot.

Twist and pull cleanly to avoid damaging the crown, which is the plant’s growth center. Never take more than one-third of the stalks at once; overharvesting weakens the plant and reduces future yields. If you see flower stalks emerging, snip them off immediately, as they divert energy from leaf production.

Use clean hands or a sharp knife to remove any damaged or yellowing leaves, but leave the younger ones to support growth. After harvesting, water the plant well and add mulch to retain moisture. This care ensures a vigorous, productive rhubarb patch year after year.

Safety Tips: Avoiding Toxic Leaves

While rhubarb stalks are delicious, the leaves are toxic and should never be eaten. They contain oxalic acid, which can cause serious health issues if ingested in large amounts.

Always trim off the leaves immediately after harvesting and discard them in the compost pile—just avoid adding them to compost meant for edible plants to prevent accidental consumption. Wash the stalks thoroughly to remove any leaf residue or dirt.

If you have pets or small children, keep harvested rhubarb out of reach and educate them about the dangers of the leaves. When cooking, use only the stalks in pies, jams, or sauces, and never substitute leaves for greens like spinach.

By following these simple safety steps, you can enjoy your rhubarb harvest worry-free. Remember, a little caution goes a long way in keeping your garden and kitchen safe.

Forcing Rhubarb for an Early Harvest

What is Rhubarb Forcing?

Forcing rhubarb is a simple trick to get sweet, tender stalks weeks earlier than usual. By blocking light from the plant, you encourage it to grow rapidly in search of sun. This results in delicate, pink stalks that are less acidic than those grown normally.

Start this process in late winter or early spring, when the first buds just begin to show. The warmth trapped inside the forcing pot accelerates growth, giving you a harvest as early as March.

It’s a fantastic way to enjoy fresh rhubarb when the rest of the garden is still dormant. Remember, forcing puts the plant under stress, so don’t force the same crown two years in a row.

Allow it to recover naturally every other year to ensure it stays healthy and productive for the long term.

How to Set Up a Forcing Pot or Box

Setting up your rhubarb for forcing is easy if you have the right tools. You can use a traditional terracotta forcing pot, a large bucket, or even a bottomless trash can. First, clear away any dead leaves around the crown to prevent rot.

Then, simply place your chosen container over the emerging buds to exclude all light. If your container has holes, plug them with straw or moss to keep the inside pitch black. To speed up the process even more, insulate the outside of the pot with straw or bubble wrap.

This traps the sun’s heat, creating a cozy microclimate for the plant. Ensure the container is secure against strong winds. Within a few weeks, you’ll see pale, tender stems pushing up, ready for your first delicious harvest of the season.

Care During the Forcing Process

While your rhubarb is busy growing undercover, it still needs a bit of attention. Check the pot occasionally to ensure it hasn’t shifted and that no light is entering, as this can ruin the blanching effect.

Keep an eye on moisture levels too; the plant may need water if the soil feels dry, especially since the container can prevent rain from reaching the roots. Water sparingly at the base to avoid rotting the crown.

The forced stalks are ready to pick when they reach about 20 to 30 cm tall. Harvest by gently pulling the stalks away from the base rather than cutting them. This minimizes damage to the crown.

Once you’ve finished harvesting, remove the cover to let the plant recover naturally for the rest of the season.

Frequently Asked Questions

Conclusion

Growing rhubarb is a rewarding and simple process that yields delicious harvests for years. Remember to harvest sparingly the first year and enjoy stalks in pies, jams, or sauces. With minimal care, rhubarb will thrive in your garden, providing fresh, tangy flavors season after season.