How to Grow and Care for Rhubarb

Rhubarb originally came from Asia and was brought to Europe in the 1600s before making its way to America. This plant has a rich history and has been a staple in many gardens, especially in cooler climates where it thrives. Historically, rhubarb was used for medicinal purposes due to its purgative properties before it became popular as a food ingredient. Over time, different varieties were cultivated to enhance its culinary qualities. Understanding its origins and historical uses can give gardeners a greater appreciation for this resilient plant and its role in garden history.

Seeds vs. Crowns

You can grow rhubarb from seeds or crowns. Growing from seeds is cheaper, but it takes longer for the plants to mature. Crowns, which are pieces of the plant with roots and buds, are faster but more expensive. Plant rhubarb in late autumn for spring growth or in early spring. When choosing between seeds and crowns, consider your timeline and budget. Seeds will require more patience as they take about a year to establish, whereas crowns will give you a quicker harvest. Additionally, using crowns from a reputable source ensures you start with a healthy plant, which can lead to better yields.

Soil Requirements

Rhubarb grows best in fertile, well-draining soil that has been enriched with compost or well-rotted manure. It prefers soil that is neutral to slightly alkaline. Choose a spot in your garden that has enough space for the plant to spread out. The soil should be well-prepared with plenty of organic matter to support the plant's growth over many years. Good drainage is crucial to prevent root rot, which can quickly damage or kill the plant. Regularly testing the soil pH and adjusting it as necessary can help create the optimal growing environment for your rhubarb.

Spacing and Location

Plant rhubarb crowns about three feet apart to give them plenty of room to grow. Rhubarb likes sunny spots but can also grow in partial shade. Some gardeners plant rhubarb near their compost piles because the soil there is very rich. The location should be free from competition with other plants, as rhubarb needs space to thrive. Ensure the site is protected from strong winds, which can damage the large leaves. Additionally, choosing a location that is easily accessible will make it more convenient to water, mulch, and harvest your rhubarb throughout the growing season.

Rhubarb needs a lot of sunlight to grow well. It does best in full sun but can also tolerate partial shade, especially in hotter climates. Make sure your rhubarb gets at least five hours of direct sunlight each day. In regions with intense summer heat, some afternoon shade can help prevent the plant from getting too stressed. The amount of sunlight directly affects the plant’s growth rate and the size of the stalks, so choosing a well-lit location is essential for a bountiful harvest.

Observing how the sun moves across your garden can help you pick the perfect spot for your rhubarb.

Water your rhubarb regularly, especially during dry periods. Newly planted rhubarb needs more water until it is well-established. Be careful not to overwater, as this can cause the roots to rot. Mulching around the plant in autumn helps retain soil moisture. Using organic mulch such as straw or wood chips not only retains moisture but also adds nutrients to the soil as it breaks down. Consistent watering is key, as irregular watering can lead to poor growth and smaller stalks.

Monitoring soil moisture levels and adjusting your watering schedule based on weather conditions will help keep your rhubarb healthy.

Use a balanced 10-10-10 fertilizer in spring and fall to give your rhubarb the nutrients it needs. Nitrogen is particularly important for leaf growth. In addition to fertilizer, apply a layer of well-rotted compost in spring to help retain moisture and improve soil fertility. Regular feeding ensures that the plant has all the necessary nutrients to produce strong, healthy stalks.

Organic fertilizers, such as fish emulsion or seaweed extract, can also be beneficial. Avoid over-fertilizing, as too much nitrogen can lead to excessive leaf growth at the expense of the stalks.

Rhubarb grows well in USDA hardiness zones three to eight. It can tolerate very low temperatures and needs a cold period in winter to thrive. Rhubarb is not suitable for very hot climates like Florida. Understanding your local climate and growing conditions is essential for successful rhubarb cultivation. In areas with mild winters, providing some artificial cooling can help mimic the natural dormancy period rhubarb requires.

Knowing your hardiness zone can also help you choose the best varieties for your area, ensuring that your rhubarb plants have the best chance to thrive and produce abundant harvests.

Prune your rhubarb by removing any flower stems that appear. This helps the plant focus its energy on growing stalks rather than flowers. Divide mature rhubarb clumps every five years to keep the plants healthy and vigorous. Regular pruning and dividing prevent overcrowding, which can lead to smaller stalks and less productive plants.

When dividing, choose healthy sections with strong roots and multiple buds for replanting. This practice not only rejuvenates the plant but also allows you to expand your rhubarb patch or share healthy divisions with friends and neighbors, promoting vigorous growth and better yields.

Harvest rhubarb by pulling and twisting the stalks from the base. Do not cut the stalks, as this can leave stumps that rot. Avoid harvesting in the first year and take only a few stalks in the second year. In established plants, you can harvest from late April to June but stop in June to avoid weakening the plant.

Proper harvesting techniques ensure the plant remains healthy and productive for many years. The best time to harvest is when the stalks are about 10 inches long and firm. Always leave some stalks behind to allow the plant to continue photosynthesis and store energy for the next growing season.

You can propagate rhubarb by dividing the roots. This is best done every five years to maintain healthy plants. Dig up the plant and use a spade to cut the root into sections, each with at least one bud. Replant the sections in fertile, moist soil. This method of propagation ensures that each new plant inherits the characteristics of the parent plant, providing consistency in growth and flavor.

Propagating rhubarb not only rejuvenates your plants but also allows you to increase your rhubarb stock or share it with fellow gardeners. Proper care during the replanting process helps the new divisions establish quickly and grow vigorously.

Rhubarb can be affected by diseases like crown rot, ramularia, and ascochyta. These diseases cause spots on the leaves and can spread to nearby plants. Remove and dispose of infected plants to prevent the spread of disease. Regular inspection of your plants can help you catch diseases early and take appropriate action. Ensuring good air circulation around the plants and avoiding waterlogged soil can reduce the risk of disease.

Using disease-resistant varieties and maintaining a clean garden environment also helps in managing and preventing common rhubarb diseases, keeping your plants healthy and productive.

Rhubarb is relatively pest-free, but slugs, snails, and other insects can occasionally be a problem. Keep the garden free from weeds and avoid overwatering to deter pests. Using barriers like copper tape around the base of the plants can help keep slugs and snails away. Natural predators such as birds and beneficial insects can also help control pest populations. Regular monitoring and early intervention are key to managing pests effectively.

In case of severe infestations, organic pest control methods like neem oil or diatomaceous earth can be used to protect your rhubarb without harming the environment.

Rhubarb’s large leaves and tall stalks make it an attractive plant in the garden. It can add height and structure, especially in garden borders. Plant rhubarb towards the perimeter of your garden or near fences for the best visual effect. Its striking foliage can create a lush, tropical look in the garden, complementing other plants and adding to the overall aesthetic. Rhubarb can also be used in decorative edible landscapes, where its functional beauty enhances the garden's appeal.

Proper placement and thoughtful garden design can turn rhubarb into a standout feature in any garden.

Swiss chard looks similar to rhubarb but has edible leaves. Knotweed, although not similar in appearance, tastes a lot like rhubarb and can be used in similar recipes. Remember, rhubarb leaves are toxic and should not be eaten. Understanding the similarities and differences between these plants can help you make informed choices for your garden. While Swiss chard offers a similar look and is entirely edible, knotweed provides an alternative flavor profile.

Growing a variety of plants with different uses and appearances can enhance your gardening experience and provide a wider range of culinary options.

Rhubarb leaves contain oxalic acid, which is toxic to humans and pets. Do not ingest the leaves, and be careful when handling them. While some suggest, not composting rhubarb leaves, oxalic acid breaks down during composting and is not harmful to the compost. Proper handling and disposal of the leaves ensure safety for everyone. Educating family members and visitors about the toxicity of rhubarb leaves can prevent accidental ingestion.

Using gloves when handling the leaves can provide additional protection. Understanding these cautions helps ensure that growing and enjoying rhubarb is a safe and rewarding experience.

There are many varieties of rhubarb to choose from, depending on your preferences and climate. Some popular varieties include:

Timperley Early: Ideal for forcing, with tender pink stems. Stockbridge Arrow: Known for long, thick stems and sweet flavor. Cawood Delight: Produces dark pink-red stems with a good shine and flavor. Victoria: An old, reliable variety with high yields and sweet flavor. Fulton's Strawberry Surprise: Newer variety with vivid red stems. Livingstone: Crops in both autumn and spring.

Each variety has its own unique characteristics, so consider your local climate and intended use when choosing which to grow. Some varieties are better suited for forcing, while others may produce larger yields or have a particular flavor profile that you prefer. Researching and experimenting with different varieties can help you find the perfect rhubarb for your garden.