How To Grow Rhubarb

There was a time when rhubarb could be found growing on the corner of almost every vegetable garden. Even if an old garden plot has been abandoned, you still might find rhubarb growing happily there. If you aren’t already growing it, give rhubarb a try!

What Is Rhubarb?

Rhubarb is a perennial vegetable that will live for years in a garden. It has the botanical name Rheum x hybridum, because most varieties today are hybrids grown for centuries. Native to parts of Europe, it’s generally hardy in U.S. Department of Agriculture Plant Hardiness Zones 3 through 7.

We call it a perennial vegetable because we eat the stalks of the plant and it comes back from the roots every year, just like a perennial flower. But for cooking, it’s most often treated like a fruit. It has a tart or sour taste, so it’s often made with fruits like strawberries, and sugar.

Are Rhubarb Leaves Poisonous?

Yes. They contain high amounts of oxalic acid. But humans can safely eat the stems.

According to the American Society for the Prevention of Cruelty to Animals (ASPCA), rhubarb is toxic to cats, dogs and horses. But because of the sour taste, they probably won’t be interested in eating it.

Rhubarb Varieties

Often you can get starter plants from another gardener who’s ready to dig up and divide their rhubarb. Several named varieties are also available:

• Victoria features green stems tinged with red, and its sweeter, milder taste is good for cooking. While most people purchase bare root plants in early spring, you can also grow this variety from seeds.
• Crimson Red, as the name suggests, features redder stems and grows up to three feet tall and wide.
• Canadian Red also has red stems.

While some online sources may sell out early, you can often find rhubarb plants for sale in person or ready to ship wherever other garden plants are sold, including Walmart, Lowe’s and your favorite local garden center.

How To Grow and Care for Rhubarb

Rhubarb grows best in full sun and rich, well-drained soil. It often grows quite large, up to three to four feet tall and wide.

Planting

Plant in early spring after adding compost or well-rotted manure to the soil. Rhubarb is considered a heavy feeder, so it needs nutrient-rich soil to grow well.

Don’t plan on harvesting any stems the first year. Give your rhubarb at least one season to become established.

Watering

Rhubarb needs about an inch of rain a week during the growing season, much like the rest of the vegetable garden. Water it during dry periods, especially the first year.

Fertilizing

Plan to add fresh compost or composted manure each spring, or add a packaged fertilizer in early spring following the directions on the label.

Harvesting

To pick rhubarb in the spring, grab a stem at the base and gently twist it off as close to the ground as possible. Cut off the leaves right away. If left on, the leaves can wilt and pull moisture out of the stems. Discard the leaves, which are poisonous.

Store harvested rhubarb in a refrigerator if you’re going to use it within a few days. You can also freeze it for use later.

In warmer climates, rhubarb season extends to mid-June. In colder zones, rhubarb can usually be picked until the end of June.

Removing flower stalks

If your rhubarb plant sends up a flower stalk, cut it off. You want your rhubarb to produce healthy roots and stems, not flowers. If your plant keeps producing stalks (aka bolting), consider giving it extra fertilizer to encourage more leaf growth.

Dividing

As a perennial, rhubarb will grow back from its roots each year. New growth starts at the outer edge of the crown of the roots.

If you notice your rhubarb plant seems bare in the center or the stems are getting narrower, it’s probably time to dig it up, divide it, and replant it. Do this in early spring before it grows new shoots. Dig up the entire clump, divide it into pieces with a sharp knife, then replant one section. Give the other sections away or plant more rhubarb for yourself.

If possible, replant in another area of the garden where the soil is rich in nutrients. Add new compost as needed.

Controlling pests

Rhubarb is rarely bothered by insects or diseases. Sweet!