Outdoor varieties - Valentine, McDonald, and German Wine. "Forced" or greenhouse varieties - Victoria and Sutton. (Roots to produce forced, rhubarb are dug outdoors in the fall and stored in a darkened shed at about 10°C until buds appear to produce an early spring crop.)
Rhubarb is a source of calcium, Vitamin C, and potassium.
One cup (250 mL) raw, diced has 27 calories.
First known references to the plant are Chinese, dated about 2700 B.C. But it probably originated in Siberia. The word rhubarb comes from the Latin rhabarbum, "near the river [the Volga] of the Barbarians".
However, until 200 hundred years ago, its value was chiefly medicinal and not culinary - it was known to make excellent purgatives and laxatives.
Not until after 1778 did it become appreciated for its fruit-like quality at times of year when most fruits were unavailable.