Rhubarb is quick to plant, simple to grow, and looks great in a perennial bed. It grows enormous leaves on long, thick stalks and provides bountiful harvests every spring for years. High-quality rhubarb can be hard to find in the store, and farmers market stands often sell out quickly. Grow your own perennial rhubarb, and you’ll never be short of this tasty treat, which is part of hundreds of recipes.
Rhubarb Overview
| Genus Name | Rheum rhabarbarum |
| Common Name | Rhubarb |
| Plant Type | Perennial, Vegetable |
| Light | Part Sun, Sun |
| Height | 2 to 3 Feet |
| Width | 3 to 4 Feet |
| Foliage Color | Blue/Green |
| Zones | 3, 4, 5, 6, 7, 8 |
| Propagation | Division, Seed |
Where to Plant Rhubarb
Rhubarb is a sun-loving perennial that can live for years, so put some thought into where you plant it. It isn’t picky about soil, although it grows best in fertile soil rich in organic matter. It requires good drainage; even clay soil is suitable as long as it is well-drained.
Beloved by northern gardeners, rhubarb tolerates frigid winters, and most varieties are cold hardy in USDA Zones 3-8. Hot summers in southern climates can cause rhubarb problems, but growers are developing heat-tolerant varieties.
While rhubarb stalks are tasty, the leaves are toxic to people and animals. Don’t plant it in areas frequented by children or pets.
How and When to Plant Rhubarb
Rhubarb crowns or divisions are usually shipped by online vendors in early spring, corresponding to your planting time. You can plant them as soon as the soil can be worked.
If you know where you will be planting rhubarb ahead of time, work aged manure and compost into the soil in the autumn before planting. Otherwise, do so in spring.
Plant root divisions 3 feet apart in rows 4 feet apart, 2-3 inches below the soil surface. If new shoots or leaves are poking up, don’t bury them. Water new plants well and provide a thick layer of mulch.
Rhubarb Care Tips
While some care is needed to produce the heaviest yields, rhubarb is self-sufficient. Give it a sunny spot with good drainage, and you’ll likely have plenty of rhubarb to harvest.
Light
Rhubarb likes full sunshine, and one look at its massive leaves confirms that. They look like giant, dark green solar panels, which is precisely what they are. Partial sun is OK, but the sunnier, the better.
Soil and Water
Rhubarb plants are heavy feeders. They aren’t picky about soil type but do best in loamy soils high in organic matter. Good drainage is essential to prevent crown root rot.
Regular water, whether from rain or irrigation, helps rhubarb grow as large and vigorous as possible, storing energy in the roots for next year’s harvest. Although drainage is essential, rhubarb enjoys consistently moist soil. Mulching around the plant can modulate soil moisture levels and keep weeds down.
Temperature and Humidity
Rhubarb prefers temperatures that stay below 75°F in summer and below 40°F in winter. In areas outside this range, it is usually grown as an annual. Rhubarb does well in average humidity and encounters problems in areas with high humidity.
Fertilizer
Apply annual side dressings of compost and aged manure for the highest rhubarb yields. These huge, leafy plants require a lot of nitrogen.
Pruning
Rhubarb doesn’t need to be pruned, but removing old foliage in autumn after it dies back lessens the chance of crown rot.
Potting and Repotting Rhubarb
Rhubarb can be grown in a 20-inch or larger container that has several drainage holes and is filled with at least five gallons of potting soil amended with a slow-release fertilizer. Because container soil dries out quickly, check it daily during hot weather. It may need to be watered every day. In winter, provide some protection from the cold by piling straw around the container, or move it into a sheltered area, such as an unheated garage, for the winter. Repotting isn’t necessary yearly, but the plant eventually becomes crowded in its pot, usually within three to five years. Divide it then and repot the divisions with fresh potting soil.
Pests and Problems
Rhubarb doesn’t suffer from many pests. Slugs can be a concern, but you can manage them with DIY beer slug traps.
Crown rot can also be a problem. Adequate drainage minimizes this issue. Dividing the crowns every four or five years can also help.
How to Propagate Rhubarb
Since rhubarb has a large crown, it is easiest to propagate it by division in spring when the new shoots are just poking above the ground, typically several weeks before your last frost date. Rhubarb can also be divided in autumn when the foliage begins to die back. Not only does dividing rhubarb every few years give you more plants, but it also reinvigorates the plant. To divide an existing rhubarb plant:
- Carefully dig around the rhubarb, lifting the entire plant free of the soil. These plants have extensive root systems, so start wide and work your way in.
- Remove any old foliage so you can see any new shoots.
- Most rhubarb clumps can be divided into several pieces. If there are natural breaks where the plant wants to come apart, take advantage of those.
- Use a soil knife or shovel to divide the clump. Try for two or three shoots on each newly divided root ball.
- Replant each new division in the garden. The crown piece should be 1-2 inches below the surface. However, if it has already started producing shoots, don’t bury the shoots, leave them poking out.
- Side dress with a couple of shovels of good compost and give them a long drink of water.
- Apply a thick layer of mulch around the new plant to control weeds and grasses. Pine straw, chopped leaves, and regular straw work well.
If you only want to take a piece of the plant and leave most of it in the ground, use your shovel to slice straight down, dividing a piece of crown with shoots from the parent plant. Replant the new piece and leave the parent in place.
Harvesting Rhubarb
Rhubarb can be lightly harvested beginning the second year after planting. Regular harvesting can begin during the third year and continue through subsequent years. Full harvests can last up to six weeks. Don’t remove more than a third of the stalks, and stop harvesting by early summer to let the plant grow and store energy for the winter and the following spring.
To harvest a stalk, grasp it at the base and twist it off at ground level. You may have to pull hard, especially on large stalks. Cutting the stems may seem more plant-friendly, but it can leave a portion of the stalk that may rot and introduce decay. Remove the leaves and compost them.
Store rhubarb stalks in the refrigerator for up to two weeks or freeze them for later use.
Types of Rhubarb
‘Chipman’s Canada Red’
Rheum rhabarbarum ‘Chipman’s Canada Red’ is a sweet, bright red-stalked plant. Its stalks are delicious as raw snacks, and they require less sugar when cooked. As the name suggests, this variety is very cold-hardy.
‘Hardy Tarty’
‘Hardy Tarty’ rhubarb is an exceptionally heat-tolerant rhubarb with red, non-stringy stalks. It has a bright, tart flavor and is slow to bolt—an excellent choice for southern gardeners who want rhubarb plants that can stand up to their warm weather.
‘Victoria’
Rheum rhabarbarum ‘Victoria’ is an old-time, heirloom rhubarb variety. This classic is a heavy producer, with long, red stalks and mild flavor. If you’re looking for the rhubarb grandma had behind the shed, this is likely it. It is an excellent choice for pies and sauces.
Rhubarb Companion Plants
Green Beans
Green beans are well known for fixing nitrogen in the soil, which is a trait rhubarb appreciates; it needs a lot of nitrogen to thrive. In addition, low-growing bush beans suppress weeds at the base of rhubarb plants.
Garlic
The strong scent of garlic and other alliums repels leaf beetles and weevils that can damage the leaves and stalks of young rhubarb plants. It is a natural fungicide in the soil and repels several garden insects, including aphids, Japanese beetles, and mites.
Catnip
Make your cat happy and attract pollinators for your rhubarb plants at the same time by adding catnip to your garden. Contain this aromatic plant in a bed or container near your rhubarb plants; when left uncontained, it can spread rapidly.