To me, nothing says Summer like sunflowers. The birds spread the seeds each fall so the next year we have volunteers coming up around the yard. Some get mowed and some are left.
We like to plant morning glories at the base of them and let them climb up. Most of our sunflowers get over 10 ft high with 4-5 heads. When they get too tall, the storms knock them down and we use the dried stalks to start campfires.