Rhubarb was used as a medication in ancient China, and is mentioned in a medical text dating from 2700 BC. It wasn't used as food until the 1600s in England, and wasn't grown in North America until the 1820s. An essential addition to the perennial food garden, rhubarb will produce year after year, and it's easy to grow from seed. Just be patient for the first year and a half after sowing, as the plants need to become established prior to harvest.