This story was originally published in 2018.
When it comes to starting rhubarb and keeping it going, it’s worth looking at the University of Maine Cooperative Extension’s bulletin on growing it in Maine. The cool-weather perennial, which is a member of the buckwheat family, thrives in northern states where it gets cold enough to force the plant into dormancy, according to Richard Brzozowski, an extension educator.
It is a good source of vitamin A, vitamin C, thiamin, riboflavin, niacin, potassium, phosphorus and dietary fiber. Starter plants are usually available at local nurseries and garden centers, he wrote, and the best way to propagate it is to split the crown of an older, established plant.
“Rhubarb crowns should be split at least every four to five years, or whenever the plant begins to produce many small stalks rather than fewer large stalks,” he wrote in the bulletin. “Rhubarb splitting and subsequent planting can be done in either the spring, when foliage is not fully mature, or in the fall, after foliage has been removed.”
When planting rhubarb, keep in mind that it does best in well-drained, loamy soil that gets full sun throughout the day, he wrote. Once rhubarb has been established, the plant is fairly drought-tolerant, but when the weather is hot and dry, it needs adequate irrigation. According to Brzozowski, that is enough water to wet the soil at least 3 to 6 inches below the surface. And when it comes to harvesting rhubarb, it’s important not to take stalks from first-year transplants, but during the second and following seasons, the stalks can be harvested whenever desired, he wrote in the bulletin.
“Allowing them to increase in thickness and height will improve quality and provide a greater mass when harvested,” Brzozowski wrote. “Generally, rhubarb can be harvested throughout the first half of summer … harvesting stalks later in the summer takes away some of the plant’s nutrient storage abilities, which can affect its survival through the winter.”
It’s important not to harvest more than half the stalks on any individual plant throughout the summer. Stalks can be harvested by pulling them with a twisting motion from the base, or else by cutting them right above the base.
