Combine bulgur and 1 1/4 cups boiling water in a large bowl. Cover and let stand 30 minutes or until bulgur is tender. Drain; return bulgur to bowl. Add cucumber and the next 4 ingredients (through onion).
Combine rind and remaining ingredients in a small bowl, stirring with a whisk. Drizzle over bulgur mixture; toss well. Cover and chill at least 1 hour.