Rhubarb is a perennial vegetable and is a relative of buckwheat. It originated in Western China, Tibet, Mongolia, Siberia, and neighboring areas. Chinese rhubarb has been traced back to 2700 BC where it was cultivated for medicinal purposes. The dried root was a popular remedy for a wide range of ills. Rhubarb was an important commodity in Europe in the 16th and 17th centuries. “In 1542 [rhubarb] was sold in France for 10 times the price of cinnamon, and in a 1657 English price list, rhubarb sold for 2.7 times more than opium.”
Culinary rhubarb was also developed in the East. It was a minor vegetable and was an ingredient in drinks and meat stews and it was not until the 18th century that rhubarb was grown for culinary purposes in Britain and America. Rhubarb became popular as sugar from the Caribbean became widely available and canning and bottling techniques improved. Early records of rhubarb in America identify an unnamed Maine gardener as having obtained seed or rootstock from Europe in the period between 1790 and 1800. He introduced it to growers in Massachusetts, where its popularity spread, and by 1822 it was sold in markets.
The northern U.S. and Canada are well suited for rhubarb production. Once planted, rhubarb plants remain productive for eight to fifteen years. Rhubarb tolerates most soils, but grows well on fertile, well-drained soils that are high in organic matter. Select a site in sun or light shade. Plant rhubarb roots in early spring while the plants are dormant. To improve vigor and leaf size, many gardeners divide the old plants and establish a new planting after at least five years of full harvest. Plants older than that tend to begin crowding themselves out. Rhubarb responds well to fertilizers; home gardeners should give each plant one cup of 10-10-10 fertilizer each spring when growth starts, applied in a circle around the plant. An application of manure or compost is beneficial in late or early winter. Do not cover the crowns.
Do not harvest rhubarb during the first year of planting; it needs all its foliage to build a strong root system. During the second year, a light harvest may be taken and normal harvests may begin in the third year. Harvest in the fall only when the plants are to be discarded the next season. If stalks and flowers develop during the spring and summer, cut them from the base of the plant as soon as they appear and discard them. To harvest, pull the stalks from the plant and trim off the leaf blades. Do not cut the rhubarb stalks from the plant, but instead snap them off. At any given time, harvest fewer than one-third of the stalks from any one plant to keep the plants healthy.
One characteristic of all types of rhubarb is that the leaf blades contain a large amount of oxalic acid, a toxic and potentially deadly poison. Only the stems are edible. Rhubarb hit by a frost or freeze can still be eaten provided the stalks are still firm and upright. If the stems ap-pear soft and mushy, do not eat them. Severe cold injury may cause the oxalic acid crystals in the leaves to migrate to the stalks, increasing the likelihood of poisoning.
Many flavors are complemented by the sourness of rhubarb. In the U.S., it is most often teamed up with strawberries and baked into pies and tarts. In England, typically it is used with ginger, while in the French cuisine it may be puréed to make sauce. Peeling the entire stalk is unnecessary; simply trim the ends and wash and dry the stalks. Always use a non-reactive pan for cooking this high-acid plant.
Use anodized aluminum, stainless steel, Teflon-coated aluminum or enamel-coated cast iron cookware.
Rhubarb can be stored in the refrigerator for several days. To freeze, chop into &h-inch pieces, spread them on a sheet pan and place in the freezer. Once frozen, slide the rhubarb into heavy-duty plastic freezer bags. Nutritionally, rhubarb is low in calories (until sugar is added), and it does not contain a great deal of fiber (only two grams per cup).
1 Clifford Foust and Dale Marshall, Culinary Rhubarb Production in North America.