During summer, garden is place where you can relax and get a new power for everyday life. No all flowers in a common garden are probably exotic but they are indeed a beautiful taste for your eyes.
I personally prefer a flower called violet alias violet odorata. These flowers has medicinal usage too. The flowers and leaves of viola are made into a syrup used in alternative medicine mainly for respiratory ailments associated with congestion, coughing, and sore throat.
If you like a beautiful smell of flowers like me than lilium is a good choice for your garden. It is originally Asian flower and lilies comprise a genus of about 110 species in thousands of wonderful color variations.