Meanwhile, in a large serving bowl, combine the arugula, chickpeas, cucumber, peppers, olives and parsley.
To cook the farro: In a medium saucepan, combine the rinsed farro with at least three cups water (enough water to cover the farro by a couple of inches). Bring the water to a boil, then reduce heat to a gentle simmer. Cook, stirring occasionally, until the farro is tender to the bite but still pleasantly chewy (pearled farro will take around 15 minutes; unprocessed farro will take 25 to 40 minutes). Drain off the excess water and return the farro to the pot. Stir in ¼ teaspoon salt and a little splash of the dressing. Set aside for just a few minutes to cool.