Rinse farro under cold water; place in medium saucepan. Add 2 1/2 cups water, 1 tsp oregano and 1/4 tsp salt. Bring to a boil over high heat. Reduce heat to medium-low; simmer, uncovered, 20 minutes or until farro is tender. Drain any additional water.
Whisk oil, vinegar, garlic, remaining 1/4 teaspoon salt, remaining 1/4 teaspoon oregano and pepper, if desired, in small bowl.
Divide farro among 4 bowls; arrange cucumber, onion, tomatoes, chickpeas and feta around farro. Drizzle with dressing.